HEATER & AIR CONDITIONING CONTROL SYSTEM

Transcription

1 VENTILTION, HETER & IR CONDITIONER SECTION HC HETER & IR CONDITIONING CONTROL SYSTEM C D CONTENTS E MNUL /C (TYPE 1) SIC INSPECTION... 4 MNUL /C IDENTIFICTION TLE... 4 pplication Table...4 DIGNOSIS ND REPIR WORKFLOW... 5 How to Perform Trouble Diagnosis For Quick nd ccurate Repair...5 INSPECTION ND DJUSTMENT... 6 Operational Check...6 FUNCTION DIGNOSIS... 7 MNUL /C IDENTIFICTION TLE... 7 pplication Table...7 FUNCTION INFORMTION... 8 Component Part Location...8 REFRIGERTION SYSTEM...10 Refrigerant Cycle...10 Refrigerant System Protection...10 MNUL IR CONDITIONER SYSTEM...11 Control System Diagram...11 Control System Description...11 Discharge ir Flow...12 Switches nd Their Control Function...13 DIGNOSIS SYSTEM (CM)...15 CONSULT-III Function (CM - COMMON ITEM)...15 CONSULT-III Function (CM - IR CONDITION- ER)...15 SELF-DIGNOSIS FUNCTION...17 Front ir Control Self-Diagnosis...17 Front ir Control Self-Diagnosis Chart...17 COMPONENT DIGNOSIS...18 MNUL /C IDENTIFICTION TLE...18 pplication Table...18 MODE DOOR MOTOR...19 System Description...19 Mode Door Motor Component Function Check...19 Mode Door Motor Diagnosis Procedure...20 IR MIX DOOR MOTOR...24 System Description...24 ir Mix Door Motor Component Function Check...25 ir Mix Door Motor Diagnosis Procedure...26 INTKE DOOR MOTOR...30 System Description...30 Intake Door Motor Component Function Check...30 Intake Door Motor Diagnosis Procedure...31 LOWER MOTOR...33 System Description...33 Front lower Motor Component Function Check...33 Front lower Motor Diagnosis Procedure...34 Front lower Motor Component Inspection...38 MGNET CLUTCH...40 System Description...40 Magnet Clutch Component Function Check...40 Magnet Clutch Diagnosis Procedure...40 INTKE SENSOR...45 System Description...45 Intake Sensor Diagnosis Procedure...45 Intake Sensor Component Inspection...46 POWER SUPPLY ND GROUND CIRCUIT FOR CONTROLLER...47 Component Description...47 Front ir Control Component Function Check...47 Front ir Control Power and Ground Diagnosis Procedure...48 ECU DIGNOSIS...49 F G H HC J K L M N O P HC-1

2 MNUL /C IDENTIFICTION TLE pplication Table IR CONDITIONER CONTROL Front ir Control Terminals Reference Values Wiring Diagram - ir Conditioner Control - With VC SYMPTOM DIGNOSIS MNUL /C IDENTIFICTION TLE pplication Table IR CONDITIONER CONTROL Symptom Matrix Chart INSUFFICIENT COOLING Component Function Check Diagnostic Work Flow Performance Chart Trouble Diagnoses for bnormal Pressure INSUFFICIENT HETING Component Function Check NOISE Component Function Check PRECUTION PRECUTIONS Supplemental Restraint System (SRS) "IR G" and "SET ELT PRE-TENSIONER" Working with HFC-134a (R-134a) Precaution for Service Equipment MNUL /C (TYPE 2) SIC INSPECTION MNUL /C IDENTIFICTION TLE pplication Table DIGNOSIS ND REPIR WORKFLOW How to Perform Trouble Diagnosis For Quick nd ccurate Repair INSPECTION ND DJUSTMENT Operational Check FUNCTION DIGNOSIS MNUL /C IDENTIFICTION TLE pplication Table FUNCTION INFORMTION Component Part Location REFRIGERTION SYSTEM Refrigerant Cycle Refrigerant System Protection MNUL IR CONDITIONER SYSTEM Control System Diagram HC-2 Control System Description Discharge ir Flow Switches nd Their Control Function DIGNOSIS SYSTEM (CM) CONSULT-III Function (CM - COMMON ITEM) CONSULT-III Function (CM - IR CONDITION- ER) COMPONENT DIGNOSIS MNUL /C IDENTIFICTION TLE pplication Table MODE DOOR MOTOR System Description Mode Door Motor Component Function Check Mode Door Motor Diagnosis Procedure IR MIX DOOR MOTOR System Description ir Mix Door Motor Component Function Check ir Mix Door Motor Diagnosis Procedure INTKE DOOR MOTOR System Description Intake Door Motor Component Function Check Intake Door Motor Diagnosis Procedure LOWER MOTOR System Description Front lower Motor Component Function Check. 101 Front lower Motor Diagnosis Procedure Front lower Motor Component Inspection MGNET CLUTCH System Description Magnet Clutch Component Function Check Magnet Clutch Diagnosis Procedure INTKE SENSOR System Description Intake Sensor Diagnosis Procedure Intake Sensor Component Inspection POWER SUPPLY ND GROUND CIRCUIT FOR CONTROLLER Component Description Front ir Control Component Function Check Front ir Control Power and Ground Diagnosis Procedure ECU DIGNOSIS MNUL /C IDENTIFICTION TLE pplication Table IR CONDITIONER CONTROL Front ir Control Terminals Reference Values Wiring Diagram - ir Conditioner Control - Without VC

3 SYMPTOM DIGNOSIS MNUL /C IDENTIFICTION TLE pplication Table IR CONDITIONER CONTROL Symptom Matrix Chart INSUFFICIENT COOLING Component Function Check Diagnostic Work Flow Performance Chart Trouble Diagnoses for bnormal Pressure INSUFFICIENT HETING Component Function Check NOISE Component Function Check PRECUTION PRECUTIONS Supplemental Restraint System (SRS) "IR G" and "SET ELT PRE-TENSIONER" Working with HFC-134a (R-134a) Precaution for Service Equipment C D E F G H HC J K L M N O P HC-3

4 MNUL /C IDENTIFICTION TLE < SIC INSPECTION > [MNUL /C (TYPE 1)] SIC INSPECTION MNUL /C IDENTIFICTION TLE pplication Table INFOID: Manual /C Type Description Visual Identification Manual /C (Type 1) Two Control Dial System [with variable blower control (VC)] WII0481ZZ Manual /C (Type 2) Three Control Dial System [without variable blower control (VC)] WII1228ZZ HC-4

5 DIGNOSIS ND REPIR WORKFLOW < SIC INSPECTION > [MNUL /C (TYPE 1)] DIGNOSIS ND REPIR WORKFLOW How to Perform Trouble Diagnosis For Quick nd ccurate Repair WORK FLOW INFOID: LISTEN TO CUSTOMER COMPLINT Listen to customer complaint. Get detailed information about the conditions and environment when the symptom occurs. >> GO TO 2 2.CHECK FOR SERVICE ULLETINS Check for any service bulletins. >> GO TO 3. 3.VERIFY THE SYMPTOM WITH OPERTIONL CHECK Verify the symptom with operational check. Refer to HC-6, "Operational Check". Can a symptom be duplicated? YES >> Go to trouble diagnosis. Refer to HC-60, "Symptom Matrix Chart". NO >> GO TO 4. 4.PERFORM THE FRONT IR CONTROL SELF-DIGNOSIS Perform front air control self-diagnosis. Refer to HC-17, "Front ir Control Self-Diagnosis". >> If any diagnostic trouble codes set. Refer to HC-17, "Front ir Control Self-Diagnosis Chart". >> Confirm the repair by performing operational check. Refer to HC-6, "Operational Check". C D E F G H HC J K L M N O P HC-5

6 INSPECTION ND DJUSTMENT < SIC INSPECTION > [MNUL /C (TYPE 1)] INSPECTION ND DJUSTMENT Operational Check INFOID: The purpose of the operational check is to confirm that the system operates properly. Conditions : Engine running and at normal operating temperature CHECKING LOWER 1. Turn blower control dial clockwise. lower should operate on low speed. 2. Turn the blower control dial again, and continue checking each blower speed until all speeds are checked. 3. Leave blower on HI speed. If NG, go to trouble diagnosis procedure for HC-34, "Front lower Motor Diagnosis Procedure". If OK, continue with next check. CHECKING DISCHRGE IR Press each mode switch and confirm that discharge air comes out according to the air distribution table. Refer tot HC-12, "Discharge ir Flow". Mode door position is checked in the next step. If NG, go to trouble diagnosis procedure for HC-20, "Mode Door Motor Diagnosis Procedure". If OK, continue with next check. NOTE: Confirm that the /C compressor clutch is engaged (sound or visual inspection) and intake door position is at fresh when the DEF ( ) or D/F ( ) is selected. CHECKING RECIRCULTION 1. Press recirculation ( ) switch one time. Recirculation indicator should illuminate. 2. Press recirculation ( ) switch one more time. Recirculation indicator should go off. 3. Listen for intake door position change (blower sound should change slightly). If NG, go to trouble diagnosis procedure for HC-31, "Intake Door Motor Diagnosis Procedure". If OK, continue with next check. NOTE: Confirm that the compressor clutch is engaged (sound or visual inspection) and intake door position is at fresh when the DEF or D/F is selected. CHECKING TEMPERTURE DECRESE 1. Rotate temperature control dial counterclockwise. 2. Check for cold air at appropriate discharge air outlets. If NG, listen for sound of air mix door motor operation if OK, go to trouble diagnosis procedure for HC-61, "Component Function Check". If air mix door motor appears to be malfunctioning, go to HC-25, "ir Mix Door Motor Component Function Check". If OK, continue with next check. CHECKING TEMPERTURE INCRESE 1. Rotate temperature control dial clockwise. 2. Check for hot air at appropriate discharge air outlets. If NG, listen for sound of air mix door motor operation. If OK, go to trouble diagnosis procedure for HC-69, "Component Function Check". If air mix door motor (front) appears to be malfunctioning, go to HC-25, "ir Mix Door Motor Component Function Check". If OK, continue with next check. CHECK /C SWITCH 1. Press /C switch with the blower switch ON. 2. /C switch indicator will turn ON. Confirm that the compressor clutch engages (sound or visual inspection). If NG, go to trouble diagnosis procedure for HC-40, "Magnet Clutch Diagnosis Procedure". If OK, continue with next check. HC-6

7 MNUL /C IDENTIFICTION TLE < FUNCTION DIGNOSIS > [MNUL /C (TYPE 1)] FUNCTION DIGNOSIS MNUL /C IDENTIFICTION TLE pplication Table INFOID: Manual /C Type Description Visual Identification C Manual /C (Type 1) Two Control Dial System [with variable blower control (VC)] D E WII0481ZZ F G Manual /C (Type 2) Three Control Dial System [without variable blower control (VC)] H HC WII1228ZZ J K L M N O P HC-7

8 FUNCTION INFORMTION < FUNCTION DIGNOSIS > [MNUL /C (TYPE 1)] FUNCTION INFORMTION Component Part Location ENGINE COMPRTMENT INFOID: WJI1489E HC-8

9 FUNCTION INFORMTION < FUNCTION DIGNOSIS > [MNUL /C (TYPE 1)] PSSENGER COMPRTMENT C D E F G H HC J K L M N O WII1198ZZ P :Front 1. Front air control M50 2. Intake sensor M Intake door motor M58 4. Variable blower control M Mode door motor M ir mix door motor M147 HC-9

10 REFRIGERTION SYSTEM < FUNCTION DIGNOSIS > [MNUL /C (TYPE 1)] REFRIGERTION SYSTEM Refrigerant Cycle INFOID: WJI1482E REFRIGERNT FLOW The refrigerant flows in the standard pattern. Refrigerant flows through the compressor, condenser, liquid tank, expansion valve, evaporator, and back to the compressor. The refrigerant evaporation through the evaporator coil is controlled by an externally equalized expansion valve, located inside the evaporator case. FREEZE PROTECTION The compressor cycles on and off to maintain the evaporator temperature within a specified range. When the evaporator coil temperature falls below a specified point, the intake sensor interrupts the compressor operation. When the evaporator coil temperature rises above the specification, the intake sensor allows compressor operation. Refrigerant System Protection INFOID: REFRIGERNT PRESSURE SENSOR The refrigerant system is protected against excessively high- or low-pressures by the refrigerant pressure sensor, located on the condenser. If the system pressure rises above or falls below the specifications, the refrigerant pressure sensor detects the pressure inside the refrigerant line and sends a voltage signal to the ECM. The ECM de-energizes the /C relay to disengage the magnetic compressor clutch when pressure on the high pressure side detected by refrigerant pressure sensor is over about 2,746 kpa (28 kg/cm 2, 398 psi), or below about 120 kpa (1.22 kg/cm 2, 17.4 psi). PRESSURE RELIEF VLVE The refrigerant system is also protected by a pressure relief valve, located in the rear head of the compressor. When the pressure of refrigerant in the system increases to an abnormal level [more than 2,990 kpa (30.5 kg/ cm 2, psi)], the release port on the pressure relief valve automatically opens and releases refrigerant into the atmosphere. HC-10

11 MNUL IR CONDITIONER SYSTEM < FUNCTION DIGNOSIS > [MNUL /C (TYPE 1)] MNUL IR CONDITIONER SYSTEM Control System Diagram INFOID: CONTROL SYSTEM The control system consists of input sensors, switches, the front air control (microcomputer) and outputs. The relationship of these components is shown in the figure below: C D E F G H HC J Control System Description CONTROL OPERTION Front air control WII1231G INFOID: K L M N O P HC-11 WII1229ZZ

12 MNUL IR CONDITIONER SYSTEM < FUNCTION DIGNOSIS > [MNUL /C (TYPE 1)] TEMPERTURE CONTROL DIL (TEMPERTURE CONTROL) Increases or decreases the set temperature. RECIRCULTION ( ) SWITCH When REC switch is ON, REC switch indicator turns ON, and air inlet is set to REC. When REC switch is turned OFF, or when compressor is turned from ON to OFF, REC switch is automatically turned OFF. REC mode can be re-entered by pressing REC switch again. REC switch is not operated when DEF switch is turned ON, or at the D/F or FOOT position. DEFROSTER ( ) SWITCH Positions the air outlet doors to the defrost position. lso positions the intake doors to the outside air position. RER WINDOW DEFOGGER SWITCH When switch is ON, rear window is defogged. OFF SWITCH (LOWER SPEED DIL) The compressor and blower are OFF. /C SWITCH (IF EQUIPPED) The compressor is ON or OFF. (Pressing the /C switch will turn off the /C switch and compressor.) MODE SWITCHES Controls the air discharge outlets. FRONT LOWER CONTROL DIL Manually controls the blower speed. MGNET CLUTCH CONTROL WJI1293E When the /C switch is pressed, or the mode switch is pressed to the DEF or D/F position, the front air control outputs a compressor ON signal to CM. The CM then sends a compressor ON signal to ECM, via CN communication line. ECM judges whether compressor can be turned ON, based on each sensor status (refrigerant pressure sensor signal, throttle angle sensor, etc.). If it judges compressor can be turned ON, it sends compressor ON signal to IPDM E/R, via CN communication line. Upon receipt of compressor ON signal from ECM, IPDM E/R turns air conditioner relay ON to operate compressor. Discharge ir Flow INFOID: HC-12

13 MNUL IR CONDITIONER SYSTEM < FUNCTION DIGNOSIS > [MNUL /C (TYPE 1)] C WJI1296E D Mode door position ir outlet/distribution Vent Foot Defroster 95% 5% 60% 40% 20% 55% 25% E F Switches nd Their Control Function SWITCHES ND THEIR CONTROL FUNCTION 15% 50% 35% 7% 15% 78% irflow always present at driver and passenger side demisters INFOID: G H HC J K L M N O P WII0271G HC-13

14 MNUL IR CONDITIONER SYSTEM < FUNCTION DIGNOSIS > [MNUL /C (TYPE 1)] WII1230G HC-14

15 DIGNOSIS SYSTEM (CM) < FUNCTION DIGNOSIS > [MNUL /C (TYPE 1)] DIGNOSIS SYSTEM (CM) CONSULT-III Function (CM - COMMON ITEM) PPLICTION ITEM CONSULT-III performs the following functions via CN communication with CM. Diagnosis mode WORK SUPPORT SELF-DIG RESULTS CN DIG SUPPORT MNTR DT MONITOR CTIVE TEST ECU IDENTIFICTION CONFIGURTION SYSTEM PPLICTION CM can perform the following functions for each system. NOTE: It can perform the diagnosis modes except the following for all sub system selection items. CONSULT-III Function (CM - IR CONDITIONER) DT MONITOR Function Description Changes the setting for each system function. Displays the diagnosis results judged by CM. Refer to CS-52, "DTC Index". Monitors the reception status of CN communication viewed from CM. The CM input/output signals are displayed. The signals used to activate each device are forcibly supplied from CM. The CM part number is displayed. Enables to read and save the vehicle specification. Enables to write the vehicle specification when replacing CM. INFOID: Diagnosis mode System Sub system selection item WORK SUPPORT DT MONITOR CTIVE TEST CM CM Door lock DOOR LOCK Warning chime UZZER Interior room lamp timer INT LMP Remote keyless entry system MULTI REMOTE ENT Exterior lamp HED LMP Wiper and washer WIPER Turn signal and hazard warning lamps FLSHER ir conditioner IR CONDITONER Combination switch COM SW Immobilizer IMMU Interior room lamp battery saver TTERY SVER Vehicle security system THEFT LM RP (retained accessory power) RETINED PWR Signal buffer system SIGNL UFFER TPMS (tire pressure monitoring system) IR PRESSURE MONITOR Panic alarm system PNIC LRM INFOID: C D E F G H HC J K L M N O P HC-15

16 DIGNOSIS SYSTEM (CM) < FUNCTION DIGNOSIS > [MNUL /C (TYPE 1)] Monitor Item [Unit] IGN ON SW [ON/OFF] FN ON SIG [ON/OFF] IR COND SW [ON/OFF] Contents Display [ignition switch position (On)/(Off), CC position (Off)] status as judged from ignition switch signal Display [FN (On)/FN (Off)] status as judged form blower fan motor switch signal Display [COMP (On)/COMP (Off)] status as judged form air conditioner switch signal HC-16

17 SELF-DIGNOSIS FUNCTION < FUNCTION DIGNOSIS > [MNUL /C (TYPE 1)] SELF-DIGNOSIS FUNCTION Front ir Control Self-Diagnosis /C SYSTEM SELF-DIGNOSIS FUNCTION The self-diagnosis function is built into the front air control to quickly locate the cause of malfunctions. INFOID: DESCRIPTION The self-diagnostic system diagnoses sensors, CN system, and battery voltage on front air control. Refer to applicable sections (items) for details. Malfunctions (if any are present) will be displayed in the form of turning ON the /C, MX /C, DEF and Intake button LED s. Refer to HC-17, "Front ir Control Self-Diagnosis Chart". SELF-DIGNOSTIC MODE C D 1. Turn ignition switch ON. 2. Press the FLOOR/DEF ( ) and DEF ( ) mode switches at the same time and release on the front air control. 3. Press the FLOOR ( ) and intake ( ) buttons within two seconds to enter self diagnostic mode. 4. The mode (VENT, FLOOR/DEF, FLOOR and VENT/FLOOR) LED s start flashing in a clockwise sequence indicating that Self test is in progress.this takes about 17 seconds to complete. 5. ll mode LED s stay ON once self test completes. 6. Malfunctions (if any) will be displayed in the form of turning ON the /C, MX /C, DEF and Intake button LED s. Refer to HC- 17, "Front ir Control Self-Diagnosis Chart". 7. To exit diagnostic mode, press any button on the front air control. Front ir Control Self-Diagnosis Chart SELF-DIGNOSTIC CHRT WII0481ZZ INFOID: E F G H HC J utton LED /C MX /C DEFROST INTKE Description Evap sensor open Evap sensor short ir mix door motor circuit malfunctioning Mode door motor circuit malfunctioning K L M N O P HC-17

18 MNUL /C IDENTIFICTION TLE < COMPONENT DIGNOSIS > [MNUL /C (TYPE 1)] COMPONENT DIGNOSIS MNUL /C IDENTIFICTION TLE pplication Table INFOID: Manual /C Type Description Visual Identification Manual /C (Type 1) Two Control Dial System [with variable blower control (VC)] WII0481ZZ Manual /C (Type 2) Three Control Dial System [without variable blower control (VC)] WII1228ZZ HC-18

19 MODE DOOR MOTOR < COMPONENT DIGNOSIS > [MNUL /C (TYPE 1)] MODE DOOR MOTOR System Description SYSTEM DESCRIPTION Component Parts Mode door control system components are: Front air control Mode door motor PR (built into mode door motor) Intake sensor INFOID: System Operation The mode door position (vent, /L, foot, D/F, and defrost) is set by the front air control by means of the mode door motor. When a mode door position is selected on the front air control, voltage is applied to one circuit of the mode door motor while ground is applied to the other circuit, causing the mode door motor to rotate. The direction of rotation is determined by which circuit has voltage applied to it, and which one has ground applied to it. The front air control monitors the mode door position by measuring the voltage signal on the PR circuit. C D E F G H HC J K WJI1314E COMPONENT DESCRIPTION Mode Door Motor The mode door motor is attached to the heater and cooling unit assembly. It rotates so that air is discharged from the outlet as indicated by the front air control. Motor rotation is conveyed to a link which activates the mode door. L M N O Mode Door Motor Component Function Check WJI1484E INFOID: P SYMPTOM: ir outlet does not change. Mode door motor does not operate normally. INSPECTION FLOW HC-19

20 MODE DOOR MOTOR < COMPONENT DIGNOSIS > [MNUL /C (TYPE 1)] 1.CONFIRM SYMPTOM Y PERFORMING OPERTIONL CHECK - DISCHRGE IR 1. Turn blower control dial to HI speed. 2. Press each mode switch and check all positions. 3. Confirm that discharge air comes out according to the air distribution table. Refer to HC-12, "Discharge ir Flow". NOTE: Confirm that the compressor clutch is engaged (visual inspection) and intake door position is at FRESH when DEF ( ) or D/F ( ) is selected. Can a symptom be duplicated? YES >> GO TO 3. NO >> GO TO 2. 2.PERFORM COMPLETE OPERTIONL CHECK Perform a complete operational check and check for any symptoms. Refer to HC-6, "Operational Check". Can a symptom be duplicated? YES >> Refer to HC-60, "Symptom Matrix Chart". NO >> System OK. 3.CHECK FOR SERVICE ULLETINS Check for any service bulletins. >> GO TO 4. 4.CHECK MODE DOOR OPERTION Check and verify mode door mechanism for smooth operation in each mode. Is inspection result normal? YES >> GO TO 5. NO >> Repair as necessary. 5.CHECK THE MODE DOOR MOTOR PR CIRCUIT Perform diagnostic procedure for the mode door motor. Refer to HC-20, "Mode Door Motor Diagnosis Procedure". Is inspection result normal? YES >> GO TO 6. NO >> Repair PR circuit or replace motor. Refer to VTL-18, "Removal and Installation". 6.RECHECK FOR SYMPTOMS Perform a complete operational check and check for any symptoms. Refer to HC-6, "Operational Check". Does another symptom exist? YES >> Repair as necessary. NO >> Replace front air control. Refer to VTL-7, "Removal and Installation". Mode Door Motor Diagnosis Procedure INFOID: SYMPTOM: ir outlet does not change. Mode door motor does not operate normally. 1.CHECK FRONT IR CONTROL FOR POWER ND GROUND HC-20

21 MODE DOOR MOTOR < COMPONENT DIGNOSIS > [MNUL /C (TYPE 1)] 1. Turn ignition switch ON. 2. Press the /L ( ) mode switch. 3. Check voltage between front air control harness connector M50 terminal 19 and terminal 20 while pressing the mode switch to the floor ( ) mode. Connector Front air control: M50 YES >> GO TO 3. NO >> GO TO 2. 2.CHECK MODE DOOR MOTOR CIRCUITS FOR SHORT TO GROUND 1. Turn ignition switch OFF. 2. Disconnect the front air control harness connector. 3. Check continuity between front air control harness connector M50 terminal 19, 20 and ground Ground : Continuity should not exist Ground : Continuity should not exist. YES >> Replace front air control. Refer to VTL-7, "Removal and Installation". NO >> Repair or replace harness as necessary. 3.CHECK FRONT IR CONTROL FOR GROUND ND POWER 1. Press the mode switch to the D/F ( ) mode. 2. Check voltage between front air control harness connector M50 terminal 19 and terminal 20 while pressing the mode switch to the vent ( ) mode. Connector Front air control: M50 YES >> GO TO 4. NO >> Replace front air control. Refer to VTL-7, "Removal and Installation". 4.CHECK MODE DOOR MOTOR ND CIRCUITS FOR OPEN 1. Turn ignition switch OFF. 2. Disconnect the front air control harness connector. 3. Check continuity between front air control harness connector M50 terminal 19 and terminal 20. YES >> GO TO 6. NO >> GO TO 5. Terminals (+) (-) Terminals (+) (-) Continuity should exist. Condition Press mode switch Condition Press mode switch Voltage (pprox.) attery voltage Voltage (pprox.) attery voltage WII0360ZZ WII0361ZZ WII0362ZZ C D E F G H HC J K L M N O P WII0363ZZ HC-21

22 MODE DOOR MOTOR < COMPONENT DIGNOSIS > [MNUL /C (TYPE 1)] 5.CHECK MODE DOOR MOTOR CIRCUITS FOR OPEN 1. Disconnect the mode door motor harness connector. 2. Check continuity between front air control harness connector M50 () terminal 19, 20 and the mode door motor harness connector M142 () terminal 1, : Continuity should exist : Continuity should exist. YES >> Replace mode door motor. Refer to VTL-18, "Removal and Installation". NO >> Repair or replace harness as necessary. 6.CHECK FRONT IR CONTROL FOR PR POWER ND GROUND 1. Reconnect front air control harness connector. 2. Turn ignition switch ON. 3. Check voltage between front air control harness connector M50 terminal 23 and terminal 3. WII1200ZZ Terminals Voltage (pprox.) Connector (+) (-) Front air control: M V YES >> GO TO 8. NO >> GO TO 7. 7.CHECK PR REFERENCE VOLTGE CIRCUIT FOR SHORT TO GROUND 1. Turn ignition switch OFF. 2. Disconnect the front air control harness connector. 3. Check continuity between front air control harness connector M50 terminal 23 and ground. Continuity should not exist. YES >> Replace front air control. Refer to VTL-7, "Removal and Installation". NO >> Repair or replace harness as necessary. 8.CHECK PR REFERENCE VOLTGE ND GROUND CIRCUITS 1. Turn ignition switch OFF. 2. Disconnect the front air control harness connector. 3. Check continuity between front air control harness connector M50 terminal 23 and terminal 3. WII1201ZZ WII1202ZZ Continuity should exist. YES >> GO TO 10. NO >> GO TO 9. 9.CHECK PR REFERENCE VOLTGE CIRCUIT FOR OPEN WII1203ZZ HC-22

23 MODE DOOR MOTOR < COMPONENT DIGNOSIS > [MNUL /C (TYPE 1)] 1. Disconnect the mode door motor harness connector. 2. Check continuity between mode door motor harness connector M142 () terminals 3, 2 and front air control harness connector M50 () terminals 3, : Continuity should exist. 3-2 : Continuity should exist. YES >> Replace mode door motor. Refer to VTL-18, "Removal and Installation". NO >> Repair or replace harness as necessary. 10.CHECK PR FEEDCK VOLTGE 1. Reconnect the front air control harness connector. 2. Turn ignition switch ON. 3. Check voltage between front air control harness connector M50 terminal 7 and ground while cycling mode switch through all modes. WII1204ZZ C D E F Voltage : pprox. 1V - 4.5V YES >> GO TO 12. NO >> GO TO CHECK PR FEEDCK SIGNL CIRCUIT FOR SHORT TO GROUND 1. Turn ignition switch OFF. 2. Disconnect front air control harness connector. 3. Check continuity between front air control harness connector M50 terminal 7 and ground. Continuity should not exist. YES >> Replace front air control. Refer to VTL-7, "Removal and Installation". NO >> Repair or replace harness as necessary. 12.CHECK PR FEEDCK CIRCUIT FOR OPEN 1. Turn ignition switch OFF. 2. Disconnect the mode door motor harness connector and front air control harness connector. 3. Check continuity between mode door motor harness connector M142 () terminal 4 and front air control harness connector M50 () terminal 7. Continuity should exist. YES >> Replace mode door motor. Refer to VTL-18, "Removal and Installation". NO >> Repair or replace harness as necessary. WII0369ZZ WII0370ZZ WII1205ZZ G H HC J K L M N O P HC-23

24 IR MIX DOOR MOTOR < COMPONENT DIGNOSIS > [MNUL /C (TYPE 1)] IR MIX DOOR MOTOR System Description SYSTEM DESCRIPTION Component Parts ir mix door control system components are: Front air control ir mix door motor PR (built into air mix door motor) Intake sensor INFOID: System Operation The front air control receives data from the temperature selected by the driver. The front air control then applies a voltage to one circuit of the air mix door motor, while ground is applied to the other circuit, causing the air mix door motor to rotate. The direction of rotation is determined by which circuit has voltage applied to it, and which one has ground applied to it. The front air control monitors the air mix door positions by measuring the voltage signal on the PR circuits of each door. WJI1316E ir Mix Door Control Specification WJI0435E COMPONENT DESCRIPTION ir Mix Door Motor HC-24

25 IR MIX DOOR MOTOR < COMPONENT DIGNOSIS > [MNUL /C (TYPE 1)] The air mix door motor is attached to the heater and cooling unit assembly. This motor rotates so that the air mix door is opened or closed to a position set by the front air control. Motor rotation is then conveyed through a shaft and the air mix door position is then fed back to the front air control by the PR built into the air mix door motor. C ir Mix Door Motor Component Function Check WJI1636E INFOID: D INSPECTION FLOW 1.CONFIRM SYMPTOM Y PERFORMING OPERTIONL CHECK - TEMPERTURE INCRESE 1. lower must be ON. 2. Turn the temperature control dial clockwise to maximum heat. 3. Check for hot air at discharge air outlets. >> GO TO 2. 2.CONFIRM SYMPTOM Y PERFORMING OPERTIONL CHECK - TEMPERTURE DECRESE 1. Turn the temperature control dial counterclockwise to maximum cold. 2. Check for cold air at discharge air outlets. Can a symptom be duplicated? YES >> GO TO 4. NO >> GO TO 3. 3.PERFORM COMPLETE OPERTIONL CHECK Perform a complete operational check and check for any symptoms. Refer to HC-6, "Operational Check". Can a symptom be duplicated? YES >> Refer to HC-60, "Symptom Matrix Chart". NO >> System OK. 4.CHECK FOR SERVICE ULLETINS Check for any service bulletins. >> GO TO 5. 5.CHECK IR MIX DOOR OPERTION Check and verify air mix door mechanism for smooth operation from maximum cold to maximum heat in each mode. YES >> GO TO 6. NO >> Repair as necessary. 6.CHECK THE IR MIX DOOR MOTOR PR CIRCUIT Perform diagnostic procedure for the air mix door motor. Refer to VTL-19, "Removal and Installation". YES >> GO TO 7. NO >> Repair PR circuit or replace air mix door motor. Refer to VTL-19, "Removal and Installation". 7.RECHECK FOR NY SYMPTOMS Perform a complete operational check for any symptoms. Refer to HC-6, "Operational Check". Does another symptom exist? E F G H HC J K L M N O P HC-25

26 IR MIX DOOR MOTOR < COMPONENT DIGNOSIS > [MNUL /C (TYPE 1)] YES NO >> Refer to HC-60, "Symptom Matrix Chart". >> Replace front air control. Refer to VTL-7, "Removal and Installation". ir Mix Door Motor Diagnosis Procedure INFOID: SYMPTOM: Discharge air temperature does not change. ir mix door motor does not operate. DIGNOSTIC PROCEDURE FOR IR MIX DOOR MOTOR 1.CHECK FRONT IR CONTROL FOR POWER ND GROUND 1. Turn ignition switch ON. 2. Rotate temperature control dial to maximum hot. 3. Check voltage between front air control harness connector M50 terminal 17 and terminal 18 while rotating temperature control dial to maximum cold. Connector Front air control: M50 Terminals (+) (-) Condition Rotate temp control dial Voltage (pprox.) attery voltage YES >> GO TO 3. NO >> GO TO 2. 2.CHECK IR MIX DOOR MOTOR CIRCUITS FOR SHORT TO GROUND 1. Turn ignition switch OFF. 2. Disconnect the front air control harness connector. 3. Check continuity between front air control harness connector M50 terminal 17, 18 and ground Ground : Continuity should not exist Ground : Continuity should not exist. YES >> Replace front air control. Refer to VTL-7, "Removal and Installation". NO >> Repair or replace harness as necessary. 3.CHECK FRONT IR CONTROL FOR POWER ND GROUND 1. Rotate temperature control dial to maximum hot. 2. Check voltage between front air control harness connector M50 terminal 17 and terminal 18 while rotating temperature control dial to maximum cold. WII0373ZZ WII0374ZZ Connector Front air control: M50 Terminals (+) (-) Condition Rotate temp control dial YES >> GO TO 4. NO >> Replace front air control. Refer to VTL-7, "Removal and Installation". 4.CHECK IR MIX DOOR MOTOR CIRCUITS FOR OPEN Voltage (pprox.) attery voltage WII0375ZZ HC-26

27 IR MIX DOOR MOTOR < COMPONENT DIGNOSIS > [MNUL /C (TYPE 1)] 1. Turn ignition switch OFF. 2. Disconnect the front air control harness connector. 3. Check continuity between front air control harness connector M50 terminal 17 and terminal 18. Continuity should exist. YES >> GO TO 6. NO >> GO TO 5. C 5.CHECK IR MIX DOOR MOTOR CIRCUITS FOR OPEN 1. Disconnect the air mix door motor harness connector. 2. Check continuity between front air control harness connector M50 () terminal 17, 18 and the air mix door motor harness connector M147 () terminal 5, : Continuity should exist : Continuity should exist. YES >> Replace air mix door motor. Refer to VTL-19, "Removal and Installation". NO >> Repair or replace harness as necessary. 6.CHECK FRONT IR CONTROL FOR PR POWER ND GROUND 1. Reconnect front air control harness connector. 2. Turn ignition switch ON. 3. Check voltage between front air control harness connector M50 terminal 23 and terminal 1. Terminals Voltage (pprox.) Connector (+) (-) Front air control: M V YES >> GO TO 8. NO >> GO TO 7. 7.CHECK PR REFERENCE VOLTGE CIRCUIT FOR SHORT TO GROUND 1. Turn ignition switch OFF. 2. Disconnect the front air control harness connector. 3. Check continuity between front air control harness connector M50 terminal 23 and ground. Continuity should not exist. YES >> Replace front air control. Refer to VTL-7, "Removal and Installation". NO >> Repair or replace harness as necessary. 8.CHECK PR REFERENCE VOLTGE ND GROUND CIRCUITS WII0376ZZ WII1206ZZ WII1223ZZ WII1202ZZ D E F G H HC J K L M N O P HC-27

28 IR MIX DOOR MOTOR < COMPONENT DIGNOSIS > [MNUL /C (TYPE 1)] 1. Turn ignition switch OFF. 2. Disconnect the front air control harness connector. 3. Check continuity between front air control harness connector M50 terminal 23 and terminal 1. Continuity should exist. YES >> GO TO 10. NO >> GO TO 9. 9.CHECK PR REFERENCE VOLTGE CIRCUIT FOR OPEN 1. Disconnect the air mix door motor harness connector. 2. Check continuity between air mix door motor harness connector M147 () terminal 3, 1 and front air control harness connector M50 () terminal 3 and terminal : Continuity should exist. 3-3 : Continuity should exist. YES >> Replace air mix door motor. Refer to VTL-19, "Removal and Installation". NO >> Repair or replace harness as necessary. 10.CHECK PR FEEDCK VOLTGE 1. Reconnect the front air control harness connector. 2. Turn ignition switch ON. 3. Check voltage between front air control harness connector M50 terminal 6 and ground while rotating temperature control dial from maximum hot to maximum cold. Voltage : pprox. 0.5V - 4.5V YES >> GO TO 12. NO >> GO TO CHECK PR FEEDCK SIGNL CIRCUIT FOR SHORT TO GROUND 1. Turn ignition switch OFF. 2. Disconnect front air control harness connector. 3. Check continuity between front air control harness connector M50 terminal 6 and ground. Continuity should not exist. YES >> Replace front air control. Refer to VTL-7, "Removal and Installation". NO >> Repair or replace harness as necessary. 12.CHECK PR FEEDCK CIRCUIT FOR OPEN WII1224ZZ WII1207ZZ WII0382ZZ WII0383ZZ HC-28

29 IR MIX DOOR MOTOR < COMPONENT DIGNOSIS > [MNUL /C (TYPE 1)] 1. Turn ignition switch OFF. 2. Disconnect the air mix door motor harness connector and front air control harness connector. 3. Check continuity between air mix door motor harness connector M147 () terminal 2 and front air control harness connector M50 () terminal 6. Continuity should exist. YES >> Replace air mix door motor. Refer to VTL-19, "Removal and Installation". NO >> Repair or replace harness as necessary. WII1208ZZ C D E F G H HC J K L M N O P HC-29

30 INTKE DOOR MOTOR < COMPONENT DIGNOSIS > [MNUL /C (TYPE 1)] INTKE DOOR MOTOR System Description SYSTEM DESCRIPTION Component Parts Intake door control system components are: Front air control Intake door motor Intake sensor INFOID: System Operation The intake door control determines the intake door position based on the position of the recirculation switch. When the recirculation switch is depressed the intake door motor rotates closing off the fresh air inlet and recirculating the cabin air. If the recirculation switch is depressed again, the intake door motor rotates in the opposite direction, again allowing fresh air into the cabin. COMPONENT DESCRIPTION Intake door motor The intake door motor is attached to the intake unit. It rotates so that air is drawn from inlets set by the front air control. Motor rotation is conveyed to a lever which activates the intake door. WJI1478E Intake Door Motor Component Function Check WJI1486E INFOID: SYMPTOM: Intake door does not change. Intake door motor does not operate normally. INSPECTION FLOW 1.CONFIRM SYMPTOM Y PERFORMING OPERTIONL CHECK - REC ( ) 1. Turn blower control dial to any speed. HC-30

31 INTKE DOOR MOTOR < COMPONENT DIGNOSIS > [MNUL /C (TYPE 1)] 2. Press vent mode ( ) switch. 3. Press REC ( ) switch. 4. Press REC ( ) switch again. 5. Listen for intake door position change (you should hear blower sound change slightly). Can a symptom be duplicated? YES >> GO TO 3. NO >> GO TO 2. 2.PERFORM COMPLETE OPERTIONL CHECK Perform a complete operational check and check for any symptoms. Refer to HC-6, "Operational Check". Can a symptom be duplicated? YES >> Refer to HC-60, "Symptom Matrix Chart". NO >> System OK. 3.CHECK FOR SERVICE ULLETINS Check for any service bulletins. >> GO TO 4. 4.CHECK INTKE DOOR OPERTION Check and verify intake door mechanism for smooth operation. Is inspection result normal? YES >> GO TO 5. NO >> Repair intake door mechanism. 5.RECHECK FOR NY SYMPTOMS Perform a complete operational check for any symptoms. Refer to HC-6, "Operational Check". Does another symptom exist? YES >> Refer to HC-60, "Symptom Matrix Chart". NO >> Replace front air control. Refer to VTL-7, "Removal and Installation". Intake Door Motor Diagnosis Procedure SYMPTOM: Intake door does not change. Intake door motor does not operate normally. DIGNOSTIC PROCEDURE FOR INTKE DOOR MOTOR 1.CHECK FRONT IR CONTROL FOR POWER ND GROUND 1. Turn ignition switch ON. 2. Check voltage between front air control harness connector M50 terminal 21 and terminal 22 while placing the front air control into self-diagnostic mode. Refer to HC-17, "Front ir Control Self-Diagnosis". INFOID: C D E F G H HC J K L M N Connector Front air control: M50 Terminals (+) (-) Condition Self-diagnostic mode Voltage (pprox.) attery voltage YES >> GO TO 3. NO >> GO TO 2. 2.CHECK INTKE DOOR MOTOR CIRCUITS FOR SHORT TO GROUND WII0397ZZ O P HC-31

32 INTKE DOOR MOTOR < COMPONENT DIGNOSIS > [MNUL /C (TYPE 1)] 1. Turn ignition switch OFF. 2. Disconnect the front air control harness connector. 3. Check continuity between front air control harness connector M50 terminal 21, 22 and ground Ground : Continuity should not exist Ground : Continuity should not exist. YES >> Replace front air control. Refer to VTL-7, "Removal and Installation". NO >> Repair or replace harness as necessary. 3.CHECK FRONT IR CONTROL FOR GROUND ND POWER 1. Press any button on the front air control to back out of self-diagnostic mode. 2. Check voltage between front air control harness connector M50 terminal 21 and terminal 22 while placing the front air control into self-diagnostic mode. Refer to HC-17, "Front ir Control Self-Diagnosis". WII0398ZZ Connector Front air control: M50 Terminals (+) (-) Condition Voltage (pprox.) YES >> GO TO 4. NO >> Replace front air control. Refer to VTL-7, "Removal and Installation". 4.CHECK INTKE DOOR MOTOR ND CIRCUITS FOR OPEN 1. Turn ignition switch OFF. 2. Disconnect the front air control harness connector. 3. Check continuity between front air control harness connector M50 terminal 21 and terminal 22. Continuity should exist. Self-diagnostic mode attery voltage YES >> Replace intake door motor. Refer to VTL-17, "Removal and Installation". NO >> GO TO 5. 5.CHECK INTKE DOOR MOTOR CIRCUITS FOR OPEN 1. Disconnect the intake door motor harness connector. 2. Check continuity between front air control harness connector M50 () terminals 21, 22 and the intake door motor harness connector M58 () terminals 1, : Continuity should exist : Continuity should exist. YES >> Replace intake door motor. Refer to VTL-17, "Removal and Installation". NO >> Repair or replace harness as necessary. WII0399ZZ WII0400ZZ WII0401ZZ HC-32

33 LOWER MOTOR < COMPONENT DIGNOSIS > [MNUL /C (TYPE 1)] LOWER MOTOR System Description INFOID: Component Parts lower speed control system components are: Front air control Variable blower control Front blower motor Front blower motor relay System Operation C D E F G H HC COMPONENT DESCRIPTION Variable lower Control The variable blower control (1) is located on the heater and cooling unit assembly. The variable blower control recieves a gate voltage from the front air control to steplessly maintain the blower motor voltage in the 0 to 5 volt range (approx.) :front. WII1209ZZ J K L M Front lower Motor Component Function Check INSPECTION FLOW WII1225ZZ INFOID: CONFIRM SYMPTOM Y PERFORMING OPERTIONL CHECK - FRONT LOWER 1. Rotate the blower control dial clockwise. lower should operate. 2. Rotate the blower control dial clockwise, and continue checking blower speed until all speeds are checked. Can the symptom be duplicated? YES >> GO TO 3. NO >> GO TO 2. N O P HC-33

34 LOWER MOTOR < COMPONENT DIGNOSIS > [MNUL /C (TYPE 1)] 2.CHECK FOR NY SYMPTOMS Perform a complete operational check for any symptoms. Refer to HC-6, "Operational Check". Does another symptom exist? YES >> Refer to HC-60, "Symptom Matrix Chart". NO >> System OK. 3.CHECK FOR SERVICE ULLETINS Check for any service bulletins. >> GO TO 4. 4.CHECK LOWER MOTOR OPERTION Check and verify blower motor operates in all speeds. Does blower motor operate in all speeds? YES >> GO TO 5. NO >> Refer to HC-34, "Front lower Motor Diagnosis Procedure". 5.CHECK ENGINE COOLNT TEMPERTURE SENSOR CIRCUIT Perform diagnostic procedure for the coolant temperature sensor circuit. Refer to EC-126, "Component Inspection" (QR25DE) or EC-580, "Component Inspection" (VQ40DE). YES >> GO TO 6. NO >> Repair or replace harness as necessary. 6.RECHECK FOR NY SYMPTOMS Perform a complete operational check for any symptoms. Refer to HC-6, "Operational Check". Does another symptom exist? YES >> Refer to HC-60, "Symptom Matrix Chart". NO >> Replace front air control. Refer to VTL-7, "Removal and Installation". Front lower Motor Diagnosis Procedure SYMPTOM: lower motor operation is malfunctioning. DIGNOSTIC PROCEDURE FOR LOWER MOTOR SYMPTOM: lower motor operation is malfunctioning under starting blower speed control. INFOID: HC-34 WII1211G

35 LOWER MOTOR < COMPONENT DIGNOSIS > [MNUL /C (TYPE 1)] 1.CHECK FUSES Check 15 fuses [No. 24 and 27 (Located in the fuse and fusible link box)]. For fuse layout. Refer to PG-77, "Terminal rrangement". Fuses are good. YES >> GO TO 2. NO >> GO TO 9. 2.CHECK FRONT LOWER MOTOR POWER SUPPLY CIRCUIT 1. Turn ignition switch OFF. 2. Disconnect front blower motor connector. 3. Turn ignition switch ON. 4. Press the /C switch. 5. Rotate blower control dial to maximum speed. 6. Check voltage between front blower motor harness connector M62 terminal 2 and ground. 2 - Ground : attery voltage YES >> GO TO 12. NO >> GO TO 3. 3.CHECK FRONT LOWER MOTOR RELY (SWITCH SIDE) POWER SUPPLY CIRCUIT 1. Turn ignition switch OFF. 2. Disconnect front blower motor relay. 3. Check voltage between front blower motor relay harness connector terminals 5,7 and ground. E54 (King Cab) E55 (Crew Cab) WJI1331E C D E F G H HC J 5, 7 - Ground : attery voltage YES >> GO TO 4. NO >> Repair harness or connector. 4.CHECK FRONT LOWER MOTOR RELY Turn ignition switch OFF. Check front blower motor relay. Refer to HC-38, "Front lower Motor Component Inspection". YES >> GO TO 5. NO >> Replace front blower motor relay. 5.CHECK FRONT LOWER MOTOR RELY (SWITCH SIDE) CIRCUIT FOR OPEN Check continuity between front blower motor relay harness connector terminals 3, 6 and front blower motor harness connector M62 terminal 2. E54 (King Cab) E55 (Crew Cab) 3, 6-2 : Continuity should exist. YES >> GO TO 6. NO >> Repair harness or connector. 6.CHECK VRILE LOWER CONTROL POWER SUPPLY CIRCUIT FOR OPEN HC-35 WJI1634E WJI1333E K L M N O P

36 LOWER MOTOR < COMPONENT DIGNOSIS > [MNUL /C (TYPE 1)] 1. Disconnect variable blower control harness connector. 2. Check continuity between front blower motor relay harness connector () terminals 3, 6 and variable blower control harness connector M121 () terminal 4. E54 (King Cab) E55 (Crew Cab) 3, 6-4 : Continuity should exist. YES >> GO TO 7. NO >> Repair harness or connector. 7.CHECK FRONT LOWER MOTOR RELY (COIL SIDE) GROUND CIRCUIT Check continuity between front blower motor relay harness connector terminal 2 and ground. E54 (King Cab) E55 (Crew Cab) WII1212ZZ 2 - Ground : Continuity should exist YES >> GO TO 8. NO >> Repair harness or connector. 8.CHECK FRONT LOWER MOTOR RELY (COIL SIDE) POWER SUPPLY 1. Turn ignition switch ON. 2. Check voltage between front blower motor relay harness connector terminal 1 and ground. E54 (King Cab) E55 (Crew Cab) WII1227ZZ 1 - Ground : attery voltage YES >> Replace variable blower control. Refer to VTL-10, "Removal and Installation". WJI1991E NO >> Repair front blower motor ground circuit or connector. 9.REPLCE FUSES Replace fuses. Does the fuse blow? YES >> If fuse blows without activating the front blower motor, repair short between fuse and front blower motor relay. If fuse blows activating the front blower motor, GO TO 10. NO >> Inspection End. 10.CHECK FRONT LOWER MOTOR POWER SUPPLY CIRCUIT FOR SHORT 1. Turn ignition switch OFF. 2. Disconnect front blower motor connector and variable blower control connector. 3. Check continuity between variable blower control harness connector M121 terminal 4 and ground. 4 - Ground : Continuity should not exist. YES >> GO TO 11. NO >> Repair harness or connector. WII0177ZZ HC-36

37 LOWER MOTOR < COMPONENT DIGNOSIS > [MNUL /C (TYPE 1)] 11.CHECK FRONT LOWER MOTOR Check front blower motor. Refer to HC-33, "Front lower Motor Component Function Check". YES >> Replace variable blower control. Refer to VTL-10, "Removal and Installation". NO >> Replace front blower motor. Refer to VTL-9, "Removal and Installation". 12.CHECK FRONT LOWER MOTOR Check front blower motor. Refer to HC-33, "Front lower Motor Component Function Check". YES >> GO TO 13. NO >> Replace front blower motor. Refer to VTL-9, "Removal and Installation". 13.CHECK LOWER MOTOR GROUND CIRCUIT 1. Disconnect variable blower control harness connector. 2. Check continuity between front blower motor harness connector M62 () terminal 1 and variable blower control harness connector M121 () terminal 2. C D E F 1-2 : Continuity should exist. YES >> GO TO 14. NO >> Repair harness or connector. 14.CHECK VRILE LOWER CONTROL POWER SUPPLY CIRCUIT FOR OPEN Check continuity between front blower motor relay harness connector () terminals 3, 6 and variable blower control harness connector M121 () terminal 4. E54 (King Cab) E55 (Crew Cab) 3, 6-4 : Continuity should exist. YES >> GO TO 15. NO >> Repair harness or connector. 15.CHECK VRILE LOWER CONTROL GROUND CIRCUIT Check continuity between variable blower control harness connector M121 terminal 1 and ground. 1 - Ground : Continuity should exist. YES >> GO TO 16. NO >> Repair harness or connector. WII0179ZZ WII1212ZZ G H HC J K L M N O 16.CHECK VRILE LOWER CONTROL SIGNL CIRCUIT WII0180ZZ P HC-37

38 LOWER MOTOR < COMPONENT DIGNOSIS > [MNUL /C (TYPE 1)] 1. Reconnect all disconnected component connectors. 2. Disconnect front air control connector. 3. Turn ignition switch ON. 4. Turn blower control dial to maximum speed. 5. check voltage between front air control harness connector M50 terminal 24 and ground Ground pprox.: 4.5V YES >> Replace front air control. Refer to VTL-7, "Removal and Installation". NO >> GO TO CHECK VRILE LOWER CONTROL SIGNL CIRCUIT 1. Turn ignition switch OFF. 2. Disconnect variable blower control. 3. Check continuity between front air control harness connector M50 () terminal 24 and variable blower control harness connector M121 () terminal : Continuity should exist. YES >> Replace variable blower control. Refer to VTL-10, "Removal and Installation". NO >> Repair harness or connector. Front lower Motor Component Inspection WII1226ZZ WII1213ZZ INFOID: COMPONENT INSPECTION Front lower Motor Relay Check continuity between terminals 3 and 5 and terminals 7 and 6 by supplying 12 volts and ground to coil side terminals 1 and 2 of the relay. LJI0068E Front lower Motor HC-38

39 LOWER MOTOR < COMPONENT DIGNOSIS > [MNUL /C (TYPE 1)] Confirm smooth rotation of the blower motor. Ensure that there are no foreign particles inside the blower unit. pply 12 volts to terminal 2 and ground to terminal 1 and verify that the motor operates freely and quietly. C WJI1508E D E F G H HC J K L M N O P HC-39

40 MGNET CLUTCH < COMPONENT DIGNOSIS > [MNUL /C (TYPE 1)] MGNET CLUTCH System Description INFOID: SYSTEM DESCRIPTION The front air control controls compressor operation based on intake temperature and a signal from ECM. Low Temperature Protection Control The front air control will turn the compressor ON or OFF as determined by a signal detected by the intake sensor. When intake air temperature is higher than 3.5 C (38.3 F), the compressor turns ON. The compressor turns OFF when intake air temperature is lower than 2.5 C (36.5 F). Magnet Clutch Component Function Check SYMPTOM: Magnet clutch does not engage. INSPECTION FLOW 1.CONFIRM SYMPTOM Y PERFORMING OPERTIONL CHECK - MGNET CLUTCH 1. Rotate blower control dial clockwise. 2. Press the vent ( ) mode switch. 3. Press /C switch. Confirm that the compressor clutch engages (sound or visual inspection). Can the symptom be duplicated? YES >> GO TO 3. NO >> GO TO 2. 2.CHECK FOR NY SYMPTOMS Perform a complete operational check for any symptoms. Refer to HC-6, "Operational Check". Does another symptom exist? YES >> Refer to HC-60, "Symptom Matrix Chart". NO >> System OK. 3.CHECK FOR SERVICE ULLETINS Check for any service bulletins. >> GO TO 4. 4.CHECK INTKE SENSOR Check and verify intake sensor circuit. Refer to HC-46, "Intake Sensor Component Inspection". >> GO TO 5. 5.RECHECK FOR NY SYMPTOMS Perform a complete operational check for any symptoms. Refer to HC-6, "Operational Check". Does another symptom exist? YES >> Refer to HC-60, "Symptom Matrix Chart". NO >> Replace front air control. Refer to VTL-7, "Removal and Installation". Magnet Clutch Diagnosis Procedure DIGNOSTIC PROCEDURE FOR MGNET CLUTCH INFOID: INFOID: HC-40