Troubleshooting Guide

Transcription

1 Troubleshooting Guide diesel - gasoline - LPG P/N June 1999 P.O. Box 1160 St. Joseph, MO Fax:

2 GENERAL INFORMATION This manual contains procedures for locating and correcting the majority of problems which may develop on the Snorkelift TB 37 Aerial Platform. Since the majority of malfunctions experienced on equipment in the aerial platform Industry are associated with the hydraulic and electrical systems, great effort has been made to develop a guide which insures that procedures regarding these areas are given the fullest possible attention and detail. As a result of these efforts, the aerial platform has been divided into twelve distinct groups with each group covered by an individual section. The Sections are as follows: 1.) Engine Diagnostics 7.) Platform Rotation System Diagnostics 2.) Hydraulic Pump Diagnostics 8.) Platform Leveling System Diagnostics 3.) Steering System Diagnostics 9.) Boom Elevation System Diagnostics 4.) Drive System Diagnostics 10.) Telescope System Diagnostics 5.) Emergency Power System Diagnostics 11.) Fuel System Diagnostics 6.) Swing System Diagnostics 12.) Accessories Diagnostics NOTES, CAUTIONS AND DANGERS The terms NOTE, CAUTION, and DANGER appear throughout this manual and have specific meanings. A NOTE provides additional or special information to make a step or procedure easier or clearer. Disregarding a NOTE might cause inconvenience, but would not cause equipment damage or personal injury. A is provided in a procedure wherever minor personal injury or equipment damage could result. Disregarding a CAUTION could cause damage to the machine; however serious personal injury is unlikely. is the most serious and emphasizes areas where personnel injury and even death could result from negligence. Permanent mechanical damage is also highly probable. DANGER signs are to be taken seriously. In some cases, serious injury or death has resulted from disregarding a DANGER. NOTE: Engine maintenance and troubleshooting information not contained in this manual may be found in the engine maintenance manual originally provided with the machine, or from the Engine Manufacture/Dealer Network. It should be recognized that every person who performs testing and diagnostic procedures and every person supervising any of these functions must be properly trained and qualified. a problem should occur which is not covered by this manual or which cannot be corrected using the listed corrective actions, technically qualified guidance from the Service Department of Snorkel International Inc., should be obtained prior to proceeding further. Tel: (816) NOTE: Diagnostic procedures basically consist of a logical process of elimination. For this reason, it is very important that the steps be performed in the order in which they are presented. Always begin by localizing the problem and defining the symptoms as accurately as possible. When the problem has been localized, make sure to completely read and comprehend the appropriate flow chart. Do not attempt to make shortcuts. 1

3 MANUAL DESIGN Each symptom described is followed by a list of inspections to be performed. Each inspection is in the form of a flowchart. A set of detailed checks are then performed at the component and/or related areas which confirm or decline the outcome. the inspection is declined the flowchart will refer to the next step to be performed until the problem is confirmed. The diagnosis then enables a determination. Example: Problem Solving Procedure Problem Example: Flowchart Procedure Troubleshoot (Identify Problem) Yes Go to step no Replace or perform repair EQUIPMENT NEEDED: Multimeter: A meter designed to read voltage, amperage and resistance. Pressure Test Gauge: A pressure gauge rated for psi. A pressure gauge rated for psi. Tachometer: A meter designed to measure engine RPM on gas and/or diesel. (Photo Tachometer is recommended) Flowmeter: A meter designed to measure fluid flow. Stopwatch: A tool designed to measure time. 2

4 SYMPTOM PAGE NUMBER Section One - Engine Diagnostics Engine starter fails to operate (No Electrical) 9 Starter disengages before engine starts 10 Engine cranks over but will not start 10 Engine starts then shuts down after 30 seconds 11 Engine will not accelerate 11 Engine over accelerates 12 Engine will not start from platform control 12 Engine starts while cranking, then dies when key switch is released 13 Section Two - Hydraulic Diagnostics Hydraulic system functions on emergency power only 39 Hydraulic pump stays on stroke 39 Hydraulic oil overheats during operation 39 Hydraulic functions are sluggish 40 Hydraulic pump will not build pressure 40 Hydraulic pump will not build enough pressure 40 Flow from hydraulic pump is too low 40 Flow from hydraulic pump is too high (kills engine) 41 Section Three - Steering System Diagnostics Machine will not steer 53 3

5 SYMPTOM PAGE NUMBER Section Four - Drive System Diagnostics Drive system is not operational with controller in either direction 61 No forward drive (Reverse ) 62 No reverse drive (Forward Ok) 62 Drive high range not operating 63 Machine drives at full speed with platform raised and/or extended 63 Brakes will not release 63 Only one wheel turns (2 wheel drive) 64 One wheel turns faster than other (2 wheel drive) 64 Section Five - Emergency Power System Diagnostics Emergency pump motor non-operational 85 No functions when on emergency power 85 Section Six - Swing System Diagnostics Swings only in one direction 93 No response from swing when platform controls are activated (Ground Controls Ok) 93 No response from swing when ground controls are activated 93 Swings erratically in either direction 94 Swings faster one way than other 94 Swing brake will not hold 94 Swings too slow 95 Section Seven - Platform Rotation System Diagnostics Platform rotate does not operate 109 Platform rotates itself 109 4

6 SYMPTOM PAGE NUMBER Section Eight - Platform Leveling System Diagnostics Platform will not maintain level as boom raises or lowers 115 Platform will not maintain level with machine off 115 Platform level will not work from ground control 115 Platform level will not work from platform control (Ground Control Ok) 116 Platform level up function is inoperative 116 Platform level down function is inoperative 116 Section Nine - Boom Elevation System Diagnostics Boom raises but will not stay elevated 129 Boom will not raise from platform control (Ground Control Ok) 129 Boom will not raise from ground control 129 Section Ten - Telescope System Diagnostics Boom will not retract from ground control 137 Boom will not retract from platform control (Ground Control Ok) 137 Boom will not extend from ground control 137 Boom will not extend from platform control (Ground Control Ok) 138 Boom drifts in 138 Section Eleven - Fuel System Diagnostics Engine will not start on gasoline, but will start on L.P. 151 Engine will not start on L.P., but will start on gasoline 151 5

7 SYMPTOM PAGE NUMBER Section Twelve - Accessories Diagnostics AC Generator will not function 159 AC Generator has low voltage 159 Machine will not steer 159 6

8 SECTION ONE: ENGINE DIAGNOSTICS

9 SECTION ONE ENGINE DIAGNOSTICS Chart 1 Engine starter fails to operate (No Electrical) Battery and Cable Connections Power Cables and Battery Disconnect Switch Step 3 Ammeter 15 Step 4 Ground Control Circuit Breaker (25 Amp) Step 5 Step 6 Emergency Stop Switch Ground Master (Key) Switch Step 7 Step 8 Ignition/Emergency Power Switch Ground/Platform Selector Switch Step 9 0 Engine Anti-Restart Relay Engine Starter Relay Starter Solenoid 19 Troubleshooting Guide 9 TB 37

10 SECTION ONE ENGINE DIAGNOSTICS Chart 2 Starter disengages before engine starts Engine Anti-Restart Relay Starter Solenoid Chart 3 Engine cranks over but will not start Ground Master (Key) Switch Ground/Platform Selector Switch Step 3 Ignition/Emergency Power Switch Step 4 Run Relay 22 Step 5 Magnetic Switch (Ford only) 23 Step 6 Magnetic Switch (Deutz only) 23 Step 7 Run Solenoid (Deutz only) 24 Troubleshooting Guide 10 TB 37

11 SECTION ONE ENGINE DIAGNOSTICS Chart 4 Engine starts then shuts down after 30 seconds Engine Temperature Gauge Engine Oil Pressure Switch Chart 5 Engine will not accelerate Throttle Circuit Breaker (15 Amp) Medium Throttle Relay (Ford only) Step 3 High Throttle Relay (Ford only) 27 Step 4 Throttle Governor or Controller (Ford only) 27 Step 5 Step 6 Step 7 Actuator (Ford only) Throttle Relay (Deutz only) Throttle Solenoid (Deutz only) Troubleshooting Guide 11 TB 37

12 SECTION ONE ENGINE DIAGNOSTICS Chart 6 Engine over accelerates Governor (Ford only) 30 Actuator (Ford only) 30 Chart 7 Engine will not start from platform control Ground/Platform Selector Switch Platform Control Circuit Breaker (20 Amp) Step 3 Emergency Stop Switch Step 4 Foot Switch 32 Step 5 Step 6 Platform Start Switch Ignition/Emergency Power Switch Troubleshooting Guide 12 TB 37

13 SECTION ONE ENGINE DIAGNOSTICS Chart 8 Engine starts while cranking, then dies when key switch is released Run Solenoid 34 Murphy Switch 34 Vacuum Switch (Ford only) 35 Troubleshooting Guide 13 TB 37

14 SECTION ONE ENGINE DIAGNOSTICS Engine starter fails to operate (No Electrical) Batteries omit hydrogen and oxygen elements that can combine explosively. Do not smoke or permit open flames or sparks when checking batteries Batteries Recharge or replace battery(s) low or no voltage Using a meter set to read voltage, check each battery for 12 volts while under load 12V corroded Check battery connections loose Power Cables and Battery Disconnect Switch Battery Disconnect Switch in Off Position Then Reset Battery Disconnect Switch to On Position Go to step 3 Clean all connections V Using a meter set to read voltage, measure voltage entering Battery Disconnect Switch Should read volts V Using a meter set to read voltage, turn Battery Disconnect Switch to On position, measure voltage coming out of Battery Disconnect Switch Should read volts low or no reading Tighten all connections Battery Disconnect Switch and/or Battery Disconnect Switch wiring Troubleshooting Guide 14 TB 37

15 SECTION ONE ENGINE DIAGNOSTICS Ammeter V Using a meter set to read voltage, measure voltage between 1.Battery Disconnect Switch and Ammeter (+) on wire # 57 2.Ammeter (-) and Circuit Breaker on wire #1A Should read volts low or no reading Step 3 Step 4 Go to step 4 Ground Control Circuit Breaker (25 Amp) Circuit breaker is open Circuit Breaker and/or Circuit Breaker wiring Using a meter set to read voltage, turn Battery Disconnect Switch to On position, measure voltage entering Emergency Stop Switch low or no reading Then Reset Circuit breaker 10-12V Check for voltage between Circuit Breaker and Emergency Stop Switch on wire #1A Should read 12 volts Go to step 5 low or no reading Circuit Breaker and/or Circuit Breaker wiring Troubleshooting Guide 15 TB 37

16 SECTION ONE ENGINE DIAGNOSTICS Emergency Stop Switch Emergency Stop Switch is off (pushed in) Then Pull Emergency Stop Switch (out) to the On position Go to step V Using a meter set to read voltage, pull Emergency Stop Switch out and measure voltage between Emergency Stop Switch and Battery side of Ground Master (Key) Switch. low or no reading Replace Emergency Stop Switch and/or Emergency Stop Switch wiring Step 5 Step 6 Ground Master (Key) Switch Go to step V Using a meter set to read voltage, activate engine starter and measure voltage between Battery post side of Ground Master Switch and start side of Ground Master Switch. low or no reading Ground Master Switch and/or Ground Master Switch wiring Troubleshooting Guide 16 TB 37

17 SECTION ONE ENGINE DIAGNOSTICS Ignition/Emergency Power Switch Go to step V Using a meter set to read voltage, activate engine starter and measure voltage between Ground Master Switch and Ignition/Emergency Power Switch low or no reading Step 7 Step 8 Ground/Platform Selector Switch Ground/Platform Selector Switch is in Platform position Then Replace Ignition/Emergency Power Switch and/or Ignition/Emergency Power Switch wiring Set Selector Switch to Ground position. Using a meter set to read voltage, activate starter and measure voltage between Ignition/Emergency Power Switch and Ground/ Platform Selector Switch Return Ground/ Platform Selector Switch to Ground position Go to step V low or no reading Replace Ground/Platform Selector Switch and/or Ground/Platform Selector Switch wiring Troubleshooting Guide 17 TB 37

18 SECTION ONE ENGINE DIAGNOSTICS Engine Anti- Restart Relay Replace wiring to Engine Anti Restart Relay low or no reading Using a meter set to read voltage, activate engine starter and measure voltage between Ground Control Switch and Anti-Restart Relay on wire #5C v Go to step v Measure voltage at wire #5B. low or no reading Step 9 Replace Engine Anti- Restart Relay still does not engage Check Adjustable Resistor between Terminal 164 and 164B, Adjust as needed for starter to engage. 0 Continuity Engine Starter Relay Check ground continuity No continuity Replace Engine Starter Relay Go to step V Using a meter set to read voltage, activate engine starter and measure voltage from 1. wire #5B to Starter Relay. 2. wire from Starter Relay to Ground low or no reading Replace Engine Starter Relay wiring Troubleshooting Guide 18 TB 37

19 SECTION ONE ENGINE DIAGNOSTICS Continuity Starter Solenoid Check ground continuity No continuity Replace Starter Solenoid 10-12V Using a meter set to read voltage, activate engine starter and measure voltage from 1. wire #5A to Starter Solenoid 2. Starter Solenoid to Ground low or no reading 1 Return to step 1 Replace Starter Solenoid wiring Troubleshooting Guide 19 TB 37

20 SECTION ONE ENGINE DIAGNOSTICS Starter disengages before engine starts Engine Anti- Restart Relay Open field in alternator Continuity Adjust resistor for longer cranking time, until engine starts and alarm shuts off. (approx. 30 seconds) Continuity Disconnect wire 164B from Alternator. Check continuity between post and alternator case. No continuity Alternator Starter Solenoid Check ground continuity No continuity Replace Starter Solenoid Return to step V Locate the adjustable resistor between terminals #164 and #164B, remove the plastic covering. While activating the starter, slowly slide adjuster until cranking time is sufficient for starting engine. Replace the plastic covering. Using a meter set to read voltage, activate engine starter and measure voltage from 1. wire #5A to Starter Solenoid 2. Starter Solenoid to Ground low or no reading Replace Starter Solenoid wiring Troubleshooting Guide 20 TB 37

21 SECTION ONE ENGINE DIAGNOSTICS Engine cranks over but will not start Ground Master (Key) Switch Go to step V Using a meter set to read voltage, activate engine starter and measure voltage between Battery post side of Ground Master Switch and ignition side of Ground Master Switch. No reading Ground Master Switch and/or Ground Master Switch wiring reading is low Check Battery Ground/Platform Selector Switch Ground/Platform Selector Switch is in Platform position Then Return Ground/ Platform Selector Switch to Ground position 10-12V Set Selector Switch to Ground position. Using a meter set to read voltage, activate starter and measure voltage between Ignition/Emergency Power Switch and Ground/ Platform Selector Switch No reading Replace Ground/Platform Selector Switch and/or Ground/Platform Selector Switch wiring reading is low Go to step 3 Check Battery Troubleshooting Guide 21 TB 37

22 SECTION ONE ENGINE DIAGNOSTICS Ignition/ Emergency Power Switch Go to step V Using a meter set to read voltage, measure voltage entering Ignition/ Emergency Power Switch low or no reading Step 3 Replace Ignition/Emergency Power Switch and/ or Ignition/Emergency Power Switch wiring low or no reading Check voltage on diode wire between Ignition/ Emergency Power Switch and Ground/Platform Switch. Replace diode wire if faulty. Measure voltage entering Run Relay (wire #4A) Step 4 Run Relay Go to step 5 (Ford) Go to step 6 (Deutz) 10-12V Using a meter set to read voltage, measure voltage between Run Relay and Murphy Switch (B Post) wire #164 low or no reading Replace Ground/Platform Selector Switch and/or Ground/Platform Selector Switch wiring Troubleshooting Guide 22 TB 37

23 SECTION ONE ENGINE DIAGNOSTICS Magnetic Switch ( Ford only) Replace Engine Spark Module Ok Using a meter set to read voltage, measure voltage on wire 1. at post NC of Magnetic Switch 2. on wire 80 between Magnetic Switch and Engine Spark Module low or no reading Step 5 Step 6 Magnetic Switch ( Deutz only) Go to step 7 Ok Replace Magnetic Switch and/or Magnetic Switch wiring Using a meter set to read voltage, measure voltage on wire #8D at post NC of Magnetic Switch low or no reading Replace Magnetic Switch and/or Magnetic Switch wiring Troubleshooting Guide 23 TB 37

24 SECTION ONE ENGINE DIAGNOSTICS Run Solenoid ( Deutz only) Repair Wire low or no reading Using a meter set to read voltage, measure voltage at wire #8D to Run Solenoid Note: Check continuity to ground on white jumper wire Ok Step 7 Replace Run Solenoid Troubleshooting Guide 24 TB 37

25 SECTION ONE ENGINE DIAGNOSTICS Engine starts then shuts down after 30 seconds Engine Temperature Gauge Repair Wire low or no reading Using a meter set to read ohms, Check continuity on wire between Murphy Switch (Black wire at S post) and Chassis ground resistance is shown Allow time for Engine to cool down Then Engine Oil Pressure Switch Engine oil pressure is due to inadequate oil level Then Fill to proper level with oil oil level is adequate engine now ok Replace Murphy Engine Temperature Gauge Remove wire #3C from Oil Pressure Switch. Restart engine engine still dies Using a meter set to read ohms, check for continuity from wire #3C to Ground Should not read continuity continuity exists Repair Wire Return to step 1 Replace Engine Oil Pressure Switch no continuity Troubleshooting Guide 25 TB 37

26 SECTION ONE ENGINE DIAGNOSTICS Engine will not accelerate Throttle Circuit Breaker (15 Amp) Circuit breaker is open Then Reset Circuit breaker Using meter set to read voltage, measure voltage Ford: entering either Medium Throttle Relay wire #55A or High Throttle Relay wire #55B Deutz: on wire #55A between Throttle Relay and Throttle Solenoid low or no reading Go to step 2 (Ford) Go to step 6 (Deutz) continuity does exists Check continuity on wire #55 between Throttle Circuit Breaker and Medium Throttle Relay or High Throttle Relay continuity does not exists Circuit Breaker and/or Circuit Breaker wiring Medium Throttle Relay (Ford only) Go to step V Using a meter set to read voltage, measure voltage on wire #55A to Throttle Controller low or no reading Check continuity on wire between Medium Throttle Relay and Throttle Controller Then wiring from Medium Throttle Relay to Throttle Controller Troubleshooting Guide 26 TB 37

27 SECTION ONE ENGINE DIAGNOSTICS High Throttle Relay (Ford only) Go to step V Using meter set to read voltage, measure voltage on wire #55B to Throttle Controller low or no reading Check continuity on wire between High Throttle Relay and Throttle Controller Then Step 3 wiring from High Throttle Relay to Throttle Controller Step 4 Electronic Governor (Ford only) Go to step V Using a meter set to read voltage, measure voltage on wire #55A and #55B going into the Electronic Governor low or no reading wiring to Electronic Governor Troubleshooting Guide 27 TB 37

28 SECTION ONE ENGINE DIAGNOSTICS Actuator Electronic Governor 10-12V Using a meter set to read voltage, measure voltage, on wire #A1 and #A2 between the Electronic Governor and Solenoid low or no reading Step 5 Electronic Governor and/or wiring Step 6 Throttle Relay (Deutz only) Go to step V Using a meter set to read voltage, measure voltage on wire #55A between Throttle Circuit Breaker and Throttle Solenoid low or no reading Check continuity on wire between Throttle Circuit Breaker and Throttle Solenoid no continuity wiring between Throttle Circuit Breaker and Throttle Solenoid Troubleshooting Guide 28 TB 37

29 SECTION ONE ENGINE DIAGNOSTICS Throttle Solenoid (Deutz) Using meter set to read voltage, measure voltage 1. on wire #55A going into Throttle Solenoid 2. on wire #55A between Throttle Solenoid and ground low or no reading Throttle Solenoid and/or Throttle Solenoid wiring problem still exists Step 7 Adjust Throttle Solenoid Troubleshooting Guide 29 TB 37

30 SECTION ONE ENGINE DIAGNOSTICS Engine over accelerates Electronic Governor Go to step V Using a meter set to read voltage, measure voltage, on wire #55A and #55B going into the Electronic Governor low or no reading Actuator Electronic Governor 10-12V Ford: wiring to Electronic Governor Using a meter set to read voltage, measure voltage on wire #A1 and #A2 between the Electronic Governor and Actuator low or no reading Electronic Governor and/or wiring Troubleshooting Guide 30 TB 37

31 SECTION ONE ENGINE DIAGNOSTICS Engine will not start from platform control Ground/Platform Selector Switch Ground/Platform Selector Switch is in Ground position Then Set Selector Switch to Platform position. Using a meter set to read voltage, activate starter and measure voltage between Ignition/Emergency Power Switch and Ground/ Platform Selector Switch Return Ground/ Platform Selector Switch to Platform position Go to step 2 Platform Control Circuit Breaker (20 Amp) Circuit Breaker is open 10-12V low or no reading Replace Ground/Platform Selector Switch and/or Ground/Platform Selector Switch wiring Using a meter set to read voltage, turn Ground/ Platform Switch to Platform position, measure voltage on wire #1 and #2 entering Platform Control Circuit Breaker Then Reset Circuit Breaker Go to step 3 Replace Circuit Breaker 10-12V low or no reading 10-12V Check for voltage on wire #1B to Emergency Stop Switch Wire #1 and/or #2 low or no reading Troubleshooting Guide 31 TB 37

32 SECTION ONE ENGINE DIAGNOSTICS Emergency Stop Switch Emergency Stop Switch is off (pushed in) Using a meter set to read voltage, pull Emergency Stop Switch out and measure voltage between Emergency Stop Switch and Battery side of Platform Master Switch. Then low or no reading Step 3 Pull Emergency Stop Switch (out) to the on position Go to step V Replace Emergency Stop Switch and/or Emergency Stop Switch wiring Step 4 Foot Switch and Wiring Make sure Foot Switch is not activated activated Go to step 5 not activated 10-12V Deactivate Foot Switch Using a meter set to read voltage, measure voltage on wire #10 going into Foot Switch and wire #8 coming out of Foot Switch Should be volts low or no voltage Foot Switch and/or wiring Troubleshooting Guide 32 TB 37

33 SECTION ONE ENGINE DIAGNOSTICS Platform Start Switch Go to step V Using a meter set to read voltage, activate Platform Start Switch and measure voltage on wire #5 between Platform Start Switch and Platform Emergency Power Switch low or no reading Replace Platform Start Switch and/or Platform Start Switch wiring Step 5 Step 6 Ignition/Emergency Power Switch Return to step V Using a meter set to read voltage, activate engine starter and measure voltage on wire #5 between Platform Master Switch and Ignition/Emergency Power Switch low or no reading Replace Ignition/Emergency Power Switch and/or Ignition/Emergency Power Switch wiring Troubleshooting Guide 33 TB 37

34 SECTION ONE ENGINE DIAGNOSTICS Engine starts while cranking, then dies when key switch is released Run Relay Go to step V Using a meter set to read voltage, measure voltage at Murphy Switch wire #164, B post of Murphy Switch low or no reading Murphy Switch Ford Go to step V Run Relay and/or Run Relay wiring Using a meter set to read voltage, measure voltage on wire Ford: on wire #80 to Spark Module Deutz: #8D between Run Solenoid and Murphy Switch Note: Check continuity to ground on white jumper wire low or no reading Replace Murphy Switch Troubleshooting Guide 34 TB 37

35 SECTION ONE ENGINE DIAGNOSTICS Vacuum Switch (Ford only) Check continuity on wire between Ignition and Solenoid when switch is in normally closed position no continuity Step 3 Replace Vacuum Switch Troubleshooting Guide 35 TB 37

36 SECTION TWO: HYDRAULIC DIAGNOSTICS

37 SECTION TWO HYDRAULICS DIAGNOSTICS Chart 1 Hydraulic system functions on emergency power only Step 3 Main Hydraulic Pump Sense Line Dump Valve Sense Line check Valve Chart 2 Hydraulic pump stays on stroke Pump Compensator 44 Chart 3 Hydraulic oil overheats during operation Functions Valve 44 Troubleshooting Guide 39 TB 37

38 SECTION TWO HYDRAULICS DIAGNOSTICS Chart 4 Hydraulic functions are sluggish Engine RPM 45 Pump Pressure 45 Step 3 Accumulator 46 Step 4 Flow from Pump 46 Chart 5 Hydraulic pump will not build pressure Pump Compensator Valve Pump Coupling Chart 6 Hydraulic pump will not build enough pressure Pump Compensator Valve Senseline Dump Valve Chart 7 Flow from hydraulic pump is too low Flow Adjustment on Main Hydraulic Pump 49 Troubleshooting Guide 40 TB 37

39 SECTION TWO HYDRAULICS DIAGNOSTICS Chart 8 Flow from hydraulic pump is too high (kills engine) Flow Adjustment on Main Hydraulic Pump 49 Troubleshooting Guide 41 TB 37

40 SECTION TWO HYDRAULICS DIAGNOSTICS Hydraulic system functions on emergency power only Main Hydraulic Pump Remove gauge and Go to step psi Install 1000 psi pressure gauge to hydraulic pump test plug. Set engine for idle and measure differential/standby pressure. Should read 300 psi Ok Replace Main Hydraulic Pump and/or Pump Coupling and/or Pump Compensator Sense Line Dump Valve Check seals on Sense Line Dump Valve bad Sense Line Dump Valve Go to step 3 malfunctioning 10-12V reading is abnormal Check Main Hydraulic Pump, Pump Coupling and Pump Compensator Using a meter set to read voltage, activate Ground Control Switch and measure voltage 1.on wire #28B between Terminal Strip in Junction Box and Sense Line Dump Valve 2.on wire # 28B at Sense Line Dump Valve low or no reading Sense Line Dump Valve and/or wiring Troubleshooting Guide 42 TB 37

41 SECTION TWO HYDRAULICS DIAGNOSTICS Sense Line Check Valve Ok Remove and inspect Sense Line Check Valve from Main Hydraulic Valve Valve should operate freely. not Step 3 Return to step 1 Replace Sense Line Check Valve Troubleshooting Guide 43 TB 37

42 SECTION TWO HYDRAULICS DIAGNOSTICS Hydraulic pump stays on stroke Hydraulic oil overheats during operation Pump Compensator Valve Check seals on Sense Line Dump Valve Functions Valve bad goes off stroke Heating continues Remove hose from compensator. Recheck pressure on Pump. stays on stroke Pump Compensator Sense Line Dump Valve Switch Manual Overrides to the On position Heating stops Functions Valve Hosing Troubleshooting Guide 44 TB 37

43 SECTION TWO HYDRAULICS DIAGNOSTICS Hydraulic functions are sluggish Engine RPM Go to step 2 correct RPM Use a Tachometer to measure Engine RPM Should read: Ford RPM at Low 2100 RPM at Mid 2800 RPM at High Deutz RPM at Low 2800 RPM at High not Adjust Throttle Actuator Pump Pressure Remove gauge and Go to step psi Install 1000 psi pressure gauge at Test Port. Set engine for idle and measure standby pressure. Should read 300 psi low or no reading Adjust Pump Compensator Troubleshooting Guide 45 TB 37

44 SECTION TWO HYDRAULICS DIAGNOSTICS Accumulator Measure the charge on the Accumulator Should be 750 to 800 psi 750 to 800 psi low or no reading Step 3 Go to step 4 Recharge Accumulator Step 4 Flow from Pump Remove gauges and Return to step 1 12 to 14 gpm and 300 psi With chassis raised (all wheels off the ground) and adequately supported, 1.Install a Flowmeter on the discharge side of pump. 2.Install a 1000 psi pressure gauge at Test Port on Accumulator. Start engine and turn Throttle Switch to high. Activate drive function full on. Flowmeter should read 12 to 14 gpm and pressure gauge should read 300 psi low or no reading Adjust Flow Ajustment Troubleshooting Guide 46 TB 37

45 SECTION TWO HYDRAULICS DIAGNOSTICS Hydraulic pump will not build pressure Pump Compensator Valve Go to step 2 low or no reading Remove hoses from Sense Line Dump Valve to Compensator Valve and reattach to Pressure Line. Using a 5000 psi pressure gauge check pressure. Should read 2800 psi 2800 psi Remove gauge and check seals on Sense Line Dump Valve bad Pump Coupling Sense Line Dump Valve Remove Main Hydraulic Pump visually check Pump Coupling bad Ok Pump Coupling Compensator and/or Main Hydraulic Pump Troubleshooting Guide 47 TB 37

46 SECTION TWO HYDRAULICS DIAGNOSTICS Hydraulic pump will not build enough pressure Pump Compensator Valve Go to step 2 low or no reading Remove hoses from Sense Line Dump Valve to Compensator Valve and reattach to Pressure Line. Using a 5000 psi pressure gauge check pressure. Should read 2800 psi 2800 psi Remove gauge and check seals on Sense Line Dump Valve bad Sense Line Dump Valve Sense Line Dump Valve Check seals on Sense Line Dump Valve bad Sense Line Dump Valve 10-12V Using meter set to read voltage, activate Ground Control Switch and measure voltage 1. On wire #28B between Terminal Strip in Junction Box and Sense Line Dump Valve 2. On wire # 28B at Sense Line Dump Valve low or no reading Sense Line Dump Valve wiring Troubleshooting Guide 48 TB 37

47 SECTION TWO HYDRAULICS DIAGNOSTICS Flow from hydraulic pump is too low Flow Adjustment on Main Hydraulic Pump Visually check Flow Adjustment Screw on Main Hydraulic Pump Screw should extend between 3/4" and 7/8" from face of pump Flow from hydraulic pump is too high (kills engine) Flow Adjustment on Main Hydraulic Pump Reset Flow Adjustment on Main Hydraulic Pump Visually check Flow Adjustment Screw on Main Hydraulic Pump Screw should extend between 3/4" and 7/8" from face of pump Reset Flow Adjustment on Main Hydraulic Pump Troubleshooting Guide 49 TB 37

48 SECTION THREE: STEERING SYSTEM DIAGNOSTICS

49 SECTION THREE STEERING SYSTEM DIAGNOSTICS Chart 1 Machine will not steer Switch for Blocking Valve Ground Signal (at steer Switch) Blocking Valve Relay and Relay Wiring Step 3 Step 4 Step 5 Step 6 Step 7 Blocking Valve Steer Switch (Right) Steer Switch (Left) Steer Control Valve Center Post Step 8 Tow Package Float Valve 57 Troubleshooting Guide 53 TB 37

50 SECTION THREE STEERING SYSTEM DIAGNOSTICS Machine will not steer Note: At this point the manual override may also be use to isolate the solenoid, however use caution as the machine will be moving. Switch for Blocking Valve Ground Signal (at steer Switch) Go to step 2 continuity Using a meter set to read continuity, activate Steer Switch and check for ground 1. on wire #100 between Steer Switch and Junction Box 2. at wire #100 in Junction Box Should show continuity to ground no continuity Replace Steer Switch and/or Steer Switch wiring Blocking Valve Relay and Wires Go to step 3 continuity Using a meter set to read continuity, activate Steer Switch and check for ground 1. on wire #100 between Terminal Strip in Junction Box and Relay 2. on wire #100 entering Relay no continuity Blocking Valve Relay and/or Blocking Valve Relay wiring Troubleshooting Guide 54 TB 37

51 SECTION THREE STEERING SYSTEM DIAGNOSTICS Note: At this point the manual override may also be use to isolate the solenoid, however use caution as the machine will be moving. Blocking Valve Visually check Blocking Valve Cartridge for binding Ok Should normally be open. stuck Step 3 Go to step 4 Blocking Valve Cartridge Step 4 Steer Switch (Right) Go to step V Using a meter set to read voltage, activate Steer Switch Right and measure voltage 1. on wire #20 between Steer Switch and Steer Control Valve 2. on wire #20 at Steer Control Valve low or no reading Replace Steer Switch (Solenoid) and/or Steer Micro (Solenoid) wiring Troubleshooting Guide 55 TB 37

52 SECTION THREE STEERING SYSTEM DIAGNOSTICS During activation of steering function the machine will be moving. Steer Switch (Left) Go to step V Using a meter set to read voltage, activate Steer Switch Left and measure voltage 1. on wire #19 between Steer Switch (Left) and Steer Control Valve 2. on wire #19 at Steer Control Valve low or no reading Replace Steer Switch (Solenoid) and/or Steer Switch (Solenoid) wiring Step 5 Step 6 Steer Control Valve Activating Manual Overrides and check pressure Should be 1500 psi approx psi lower than 1500 psi Go to step 7 Readjust to 1500 psi Troubleshooting Guide 56 TB 37

53 SECTION THREE STEERING SYSTEM DIAGNOSTICS During activation of steering function the machine will be moving. Center Post Steer Cylinder Note: Machines with optional Tow Package go to step 8 reading is normal Remove hoses leading to Steer Cylinder Plug hoses and cap the Steer Cylinder. While activating steering function, check for 1500 psi at the pump pressure Test Port reading is abnormal Center Post Step 7 Step 8 Tow Package Float Valve Refer to Chapter 12 Accessories Diagnostics Troubleshooting Guide 57 TB 37

54 SECTION FOUR: DRIVE SYSTEM DIAGNOSTICS

55 SECTION FOUR DRIVE SYSTEM DIAGNOSTICS Chart 1 Drive system is not operational with controller in either direction Foot Switch Drive Circuit Breaker (3 amp) Step 3 Controller Circuit Board and S1 Micro Switch Wiring Step 4 S1 Micro-Switch (in Controller) Step 5 Controller Circuit Board 67 Step 6 Step 7 Potentiometer S2 Micro-Switch (in Controller) Step 8 Step 9 Drive Solenoid Drive Control Valve Center Post 69 1 Shuttle Valve Portion of Dual Counterbalance Valve 70 Troubleshooting Guide 61 TB 37

56 SECTION FOUR DRIVE SYSTEM DIAGNOSTICS Chart 2 No forward drive (reverse ok) S2 Micro-Switch (in Drive Controller) Drive Controller Circuit Board Step 3 Solenoid (Drive Forward on Control Valve) Step 4 Dual Counterbalance Cartridge Chart 3 No reverse drive (forward ok) S2 Micro-Switch (in Drive Controller) Drive Controller Circuit Board Step 3 Solenoid Valve (Drive reverse on Control Valve) Step 4 Dual Counterbalance Cartridge Troubleshooting Guide 62 TB 37

57 SECTION FOUR DRIVE SYSTEM DIAGNOSTICS Chart 4 Drive high range not operating Drive Low/High Range Switch Boom Position and/or Boom Limits Switch Step 3 Range Valve 76 Step 4 Selector Spool in Transmission Package Step 5 Power to R Terminal Chart 5 Machine drives at full speed with platform raised and/or extended Boom Limits Switch 78 Range Valve 78 Chart 6 Brakes will not release Brake Pressure 79 Troubleshooting Guide 63 TB 37

58 SECTION FOUR DRIVE SYSTEM DIAGNOSTICS Chart 7 Only one wheel turns (2 wheel drive) Case Drain 80 Flow Divider 80 Chart 8 One wheel turns faster than other (2 wheel drive) Case Drain 81 Flow Divider 81 Troubleshooting Guide 64 TB 37

59 SECTION FOUR DRIVE SYSTEM DIAGNOSTICS Drive system is non-operational with controller in either direction Foot switch Go to step V Using a meter set to read voltage, activate Foot Switch and measure voltage 1. on wire #9 between Foot Switch and Drive Circuit Breaker 2. at 3 amp Drive Circuit Breaker low or no voltage Drive Circuit Breaker (3 amp) Go to step V Replace Foot Switch and/or Foot Switch wiring Using a meter set to read voltage, activate Foot Switch and measure voltage 1. on wire #69 between Circuit Breaker and Drive Controller 2. at positive (+) post of Drive controller low or no voltage Replace Foot Switch and/or Foot Switch wiring Troubleshooting Guide 65 TB 37

60 SECTION FOUR DRIVE SYSTEM DIAGNOSTICS Controller Circuit Board and S1 Micro-Switch Wiring Go to step V Using a meter set to read voltage, activate Foot Switch and measure voltage 1. on red wire from Circuit Board to S1 Micro-Switch 2. at red wire of S1 Micro-Switch low or no voltage Step 3 Replace Circuit Board and/or S1 Micro-Switch wiring Step 4 S1 Micro-Switch (in Controller) lit Move controller handle in either direction and observe red LED on Circuit Board Controller Go to step 5 not lit Replace S1 Micro-Switch (in Controller) and/or S1 Micro-Switch wiring Go to step 5 low or no voltage 10-12V Using a meter set to read voltage, step on Foot Switch and activate Controller, measure voltage 1. on black wire between S1 Micro-Switch and Controller Circuit Board 2. at point where black wire from S1 Switch enters Controller Circuit Board Troubleshooting Guide 66 TB 37

61 SECTION FOUR DRIVE SYSTEM DIAGNOSTICS Controller Circuit Board Go to step V Using a meter set to read voltage, step on Foot Switch and activate Controller, measure voltage 1. on green wire to Potentiometer from Controller Circuit Board 2. on wire between Controller Circuit Board and Potentiometer low or no voltage Step 5 Step 6 Potentiometer Go to step 7 continuity Replace Controller Circuit Board and/or Controller Circuit Board wiring Using a meter set to ohms, measure reading across 1. green wire and purple wire between Controller Circuit Board and Potentiometer 2. green wire and orange wire between Controller Circuit Board and Potentiometer Reading should vary according to Controller movement Replace Potentiometer and/or Potentiometer wiring No continuity no reading Check continuity on wire between Controller Circuit Board and Potentiometer Troubleshooting Guide 67 TB 37

62 SECTION FOUR DRIVE SYSTEM DIAGNOSTICS Machine function will be moving when manual override is activated. Continuity S2 Micro-Switch (in Controller) Check continuity on blue wire and on white wire between Controller Circuit Board and S2 Micro-Switch No Continuity Replace S2 Micro-Switch and/or S2 Micro-Switch wiring Go to step 8 no reading Using a meter set to read voltage, step on Foot Switch and activate Controller, perform the following: 1. While activating controller in forward mode measure proportional voltage at Controller Circuit Board where white wire enters from S2 Micro-Switch 2. While activating Controller in reverse mode measure proportional voltage at Controller Circuit Board where blue wire enters from S2 Micro-Switch Reading should vary according to amount of reverse movement Step 7 Step 8 Drive Solenoid Go to step 9 functions are normal Push Manual Override while activating various controller functions and check operation. functions are abnormal or erratic Replace Drive Section Control Valve Troubleshooting Guide 68 TB 37

63 SECTION FOUR DRIVE SYSTEM DIAGNOSTICS Drive Control Valve Remove gauge and Go to step 10 functions are normal Remove hoses from drive section of Control Valve. Plug the hoses and cap valve. Install a 5000 psi pressure gauge to Pump Test Port. While activating drive control function, check pressure. Should read 2800 psi (while activating function) functions are abnormal or erratic Step 9 Replace Valves on Drive Section of Control Valve 0 Center Post Remove gauge and Go to step 11 pressures are normal Remove hoses at V1 and V2 ports of Dual Counterbalance Valve. Plug hoses and cap valve. Install a 5000 psi pressure test gauge to Pump Test Port While activating drive control function, check pressure. Should read 2800 psi (while activating function) pressures are abnormal or erratic Center Post Troubleshooting Guide 69 TB 37

64 SECTION FOUR DRIVE SYSTEM DIAGNOSTICS Shuttle Valve Portion of Dual Counterbalance Valve Install a 5000 psi pressure test gauge to BR port of Dual Counterbalance Valve. Note if pressure is equal to drive pressure. 1 Return to step 1 equal pressure unequal pressure Replace Shuttle Valve (in Dual Counterbalance Valve) Troubleshooting Guide 70 TB 37

65 SECTION FOUR DRIVE SYSTEM DIAGNOSTICS No forward drive (Reverse Ok) S2 Micro-Switch (in Drive Controller) Go to step 2 normal Using a meter set to read voltage, activate function and measure proportional voltage at Controller Circuit Board at point where blue wire from S2 Micro-Switch enters. Reading should vary according to controller movement. Replace S2 Micro-Switch and/or S2 Micro-Switch wiring Drive Controller Circuit Board Go to step 3 no continuity normal low or no reading Check continuity on blue wire between S2 Micro- Switch and Controller Circuit Board Using a meter set to read voltage, activate drive function and measure proportional voltage at Terminal A of Circuit Board. Reading should vary according to controller movement. no or erratic reading Replace Drive Controller Circuit Board Troubleshooting Guide 71 TB 37

66 SECTION FOUR DRIVE SYSTEM DIAGNOSTICS Machine function will be moving when manual override is activated. Solenoid Valve (Drive forward on Control Valve) Using a meter set to read voltage. While activating forward function, measure proportional voltage at wire #17 on Drive section of Control Valve. Reading should vary according to controller movement. no reading Try manual override Override allows operation Step 3 Go to step 4 Override does not allow operation Replace Drive Forward Solenoid Valve and/or Drive Forward Solenoid Valve wiring Step 4 Dual Counterbalance Valve Cartridge Using a 5000 psi pressure test gauge activate drive function and check system pressure at hose entering port M1 on Counterbalance Valve no pressure reading Replace the Dual Counterbalance Valve Cartridge tested Troubleshooting Guide 72 TB 37

67 SECTION FOUR DRIVE SYSTEM DIAGNOSTICS No reverse drive (Forward Ok) S2 Micro-Switch (in Drive Controller) Go to step 2 normal Using a meter set to read voltage, activate reverse function and measure proportional voltage at Controller Circuit Board at point where white wire from S2 Micro-Switch enters. Reading should vary according to controller movement. Replace S2 Micro-Switch and/or S2 Micro-Switch wiring No continuity low or no reading Check continuity on white wire between S2 Micro- Switch and Controller Circuit Board Drive Controller Circuit Board Go to step 3 normal Using a meter set to read voltage, activate reverse function and measure proportional voltage at Terminal B of Controller Circuit Board Reading should vary according to controller movement no or erratic reading Replace Drive Controller Circuit Board Troubleshooting Guide 73 TB 37

68 SECTION FOUR DRIVE SYSTEM DIAGNOSTICS Machine function will be moving when manual override is activated. Solenoid Valve (Drive reverse on Control Valve) Using a meter set to read voltage. While activating reverse function, measure proportional voltage at wire #18 on Drive section of Control Valve. Reading should vary according to controller movement. no reading Try manual override Step 3 Step 4 Go to step 4 Dual Counterbalance Valve Cartridge Override does not allow operation Override allows operation Replace Drive Reverse Solenoid Valve and/or Drive Reverse Solenoid Valve wiring Using pressure test gauge activate drive function and check system pressure at hose entering port M2 on Counterbalance Valve no pressure reading Replace the Dual Counterbalance Valve Cartridge tested Troubleshooting Guide 74 TB 37

69 SECTION FOUR DRIVE SYSTEM DIAGNOSTICS Drive high range not operating Drive Low/High Range Switch Go to step 2 low or no reading Using a meter set to read voltage, measure voltage on wire #16A going into the Low/High Drive Range Switch 10-12V Go to step V Measure voltage on wire #11 coming out of the Low/High Drive Range Switch. low or no reading Boom Position and/or Boom Limit Switch Replace Drive Low/High Range Switch and/or Drive Low/High Range Switch wiring Booms are not positioned for High Range speed operations Boom Limit Switch are not Adjusted Boom Extend Limit Switch and/or wiring Boom Up Limit Switch and/or wiring Wiring to Drive Low/High Range Switch no voltage no voltage 10-12V Position Booms to fully retracted and down position. Adjust Boom Retract/Down Limit Switch still not operating Check for volts at wire #70A at Boom Extend Limit Switch 10-12V Check for volts on wire #16A at Boom Up Limit Switch Troubleshooting Guide 75 TB 37

70 SECTION FOUR DRIVE SYSTEM DIAGNOSTICS Range Valve Using meter set to read voltage, measure voltage at Range Valve wire #34. no reading 10-12V Wiring to Range Valve Check for blockage in Drive Range Valve and/or hoses pressure is low Using a 5000 psi pressure gauge, measure pressure on hose between Range Valve and Center Post. Should read Drive Pressure Ok Step 3 Go to step 4 Step 4 Selector Spool in Transmission Package Go to step 5 speeds are reached and Selector Spool is shifting Verify that Selector Spool is shifting by checking drive speed. Should be mph. deactivated and 2-3 mph. activated. (3 mph = 100 ft in 22 sec) speeds are and Selector Spool is not shifting Selector Spool in Transmission Package Troubleshooting Guide 76 TB 37

71 SECTION FOUR DRIVE SYSTEM DIAGNOSTICS Power to R Terminal Check connection on Boom Wire between Boom Switches and Platform low With Boom retracted and lowered, use a meter set to read voltage, measure voltage at the R Terminal of Drive Controller no reading Return to step V Adjust High Speed Trim Pot on controller to get 3 mph ft in 22 sec. Step 5 Troubleshooting Guide 77 TB 37

72 SECTION FOUR DRIVE SYSTEM DIAGNOSTICS Machine drives at full speed with platform raised and/or extended Boom Limits Switch Boom Limits Switch are sticking or not properly Adjusted Go to step 2 problem still exists Repair, replace or readjust Boom Limits Switch Range Valve Using a 5000 psi pressure gauge, measure pressure on hose between Range Valve and Center Post Should read 0 psi 0 psi Drive pressure Range Valve Check for stuck Selector Valve on Transmission Package Troubleshooting Guide 78 TB 37

73 SECTION FOUR DRIVE SYSTEM DIAGNOSTICS Brakes will not release Brake Pressure 1. Install a 5000 psi pressure gauge in BR Port on Motion Control Valve 2. Take pressure reading at Pump Compensator Readings should be similar Brake Shuttle Valve Troubleshooting Guide 79 TB 37

74 SECTION FOUR DRIVE SYSTEM DIAGNOSTICS Only one wheel turns (2 wheel drive) Note: Make sure Hubs are engaged. Case Drain Go to step 2 less than.5 gpm Disconnect existing hose, install a flowmeter between existing hose and Drive Motor. Should be no more than.5 gpm while driving more than.5 gpm Drive Motor Flow Divider as needed Ok Remove Flow Divider from Drive Control Valve. Visually check for broken springs bad Relief Valve in Drive Control Valve Troubleshooting Guide 80 TB 37

75 SECTION FOUR DRIVE SYSTEM DIAGNOSTICS One wheel turns faster than other (2 wheel drive) Case Drain Go to step 2 less than.5 gpm Disconnect existing hose, install a flowmeter between existing hose and Drive Motor. Should be no more than.5 gpm more than.5 gpm Drive Motor Flow Divider as needed Ok Remove Flow Divider from Drive Control Valve. Visually check for broken springs bad Relief Valve in Drive Control Valve Troubleshooting Guide 81 TB 37

76 SECTION FIVE: EMERGENCY POWER SYSTEM DIAGNOSTICS

77 SECTION FIVE EMERGENCY POWER SYSTEM DIAGNOSTICS Chart 1 Emergency pump motor nonoperational Battery and Cable Connections Emergency Power Switch Step 3 Emergency Power Solenoid and Wiring Step 4 Emergency Power Unit Chart 2 No functions when on emergency power Battery and Cable Connections Emergency Power Pump Step 3 Blocking Valve 89 Troubleshooting Guide 85 TB 37

78 SECTION FIVE EMERGENCY POWER SYSTEM DIAGNOSTICS Emergency pump motor non-operational Batteries omit hydrogen and oxygen elements that can combine explosively. Do not smoke or permit open flames or sparks when checking batteries Batteries Recharge or replace battery(s) low or no voltage Using a meter set to read voltage, check each battery for 12 volts while under load 12V corroded Check battery connections loose Emergency Power Switch Go to step 3 Repair or Replace Emergency Power Switch Terminal wiring (wire #6) and/or Emergency Power Solenoid wiring (wire #6A) and/or Emergency Power Switch Clean all connections 10-12V No continuity Tighten all connections Using a meter set to read voltage, activate Emergency Power and measure voltage 1. on wire #6 of Emergency Power Switch 2. at Emergency Power Solenoid Should be volts no reading Check continuity 1. on wire #6 between Emergency Power Switch and Terminal Strip in Control Box 2. between wire #6 of Terminal Strip in Junction Box and wire #6A at Emergency Power Solenoid Troubleshooting Guide 86 TB 37

79 SECTION FIVE EMERGENCY POWER SYSTEM DIAGNOSTICS Emergency Power Solenoid and Wiring Go to step V Using a meter set to read voltage, measure voltage 1. at Emergency Power Solenoid and from Battery Disconnect Switch 2. activate Emergency Power Switch and measure voltage at Emergency Pump Motor Should be volts Step 3 Repair or Replace Wiring from Battery Disconnect Switch to Emergency Power Solenoid and/or Emergency Power Unit wiring and/or Emergency Power Solenoid No continuity no reading Check continuity 1. on wire between Battery Disconnect Switch and Emergency Power Solenoid 2. on wire between Emergency Power Solenoid and Pump Motor Step 4 Emergency Power Unit previous checks have been performed and found to be normal, check Emergency Pump Motor for internal grounding condition Repair or Replace Emergency Pump Motor Troubleshooting Guide 87 TB 37

80 SECTION FIVE EMERGENCY POWER SYSTEM DIAGNOSTICS No functions when on emergency power Batteries omit hydrogen and oxygen elements that can combine explosively. Do not smoke or permit open flames or sparks when checking batteries Batteries Recharge or replace battery(s) low or no voltage Using a meter set to read voltage, check each battery for 12 volts while under load 12V corroded Check battery connections loose Emergency Power Pump Remove gauge and Go to step 3 Clean all connections Ok Tighten all connections Attach 5000 psi pressure gauge to discharge side of Emergency Power Pump, activate Emergency Power Pump and Ground Control Switch or Foot Switch. Should read 3000 psi. reading is abnormal or erratic Repair or Replace Emergency Power Pump Unit Troubleshooting Guide 88 TB 37

81 SECTION FIVE EMERGENCY POWER SYSTEM DIAGNOSTICS Blocking Valve Refer back to Chapter 3, Chart 1 Step 3 no voltage With Ground Control Switch activated, use a meter set to read voltage and measure voltage on wire #100B to Blocking Valve Solenoid Should be 10 to 12 volts 10 to 12V Step 3 Blocking Valve Cartridge Troubleshooting Guide 89 TB 37