- WK - JEEP GRAND CHEROKEE -.7L MAGNUM V6 P44- SENSOR INTERMITTENT S4 S4 S9 EXCEPT 6.L 6.L F856 YL/PK K9 DB/DG F855 PK/YL F855 8 K9 PK/YL DB/DG CRANKSHAFT 5.7/6.L.7L.7L 5.7L/6.L F856 YL/PK K44 GY/DB K44 K9 DB/GY DB/DG F855 PK/YL K4 BR/LB K4 BR 7 C 4 C 7 C 9 C 5 C 5 VOLT CMP SENSOR 5 VOLT CKP SUPPLY SIGNAL GROUND SUPPLY SIGNAL MODULE- POWERTRAIN CONTROL 5.7L/6.L.7L BLACK/ORANGE CRANKSHAFT (.7L) BLACK/BLACK 8 MODULE- POWERTRAIN CONTROL C 9 8 9 MODULE- POWERTRAIN CONTROL C CRANKSHAFT (5.7L/6.L) 4987 For a complete wiring diagram, refer to the Wiring Information. When Monitored: While cranking the engine and engine running. Set Condition:
When the failure counter reaches. One Trip Fault. Three good trips to turn off the MIL. Possible Causes (F856) 5-VOLT SUPPLY CIRCUIT OPEN (F856) 5-VOLT SUPPLY CIRCUIT SHORTED TO GROUND (K44) CMP SIGNAL CIRCUIT SHORTED TO VOLTAGE (K44) CMP SIGNAL CIRCUIT OPEN (K44) CMP SIGNAL CIRCUIT SHORTED TO GROUND (K44) CMP SIGNAL CIRCUIT SHORTED TO THE (F856) 5-VOLT SUPPLY CIRCUIT TONE WHEEL/PULSE RING SENSOR POWERTRAIN CONTROL MODULE (PCM) Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 8 - DTC-Based Diagnostics/MODULE,. ACTIVE DIAGNOSTIC TROUBLE CODE (DTC). Turn the ignition on.. Using the scan tool, read DTCs. Copy DTC and Freeze Frame information.. Start the engine and allow it to reach operating temperature. WARNING: NOTE: When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts or fan. Do not wear loose clothing. Failure to follow these instructions may result in possible serious or fatal injury. Attempt to operate the vehicle under conditions similar to which the DTC was set. NOTE: It may be necessary to test drive the vehicle within the DTC monitoring conditions in order for this DTC to set. 4. With a scan tool, read the active DTCs. Is the DTC Active at this time? Yes Go To No Perform the INTERMITTENT CONDITION diagnostic procedure. (Refer to 8 - DTC-Based Diagnostics/ MODULE,. CHECKING SENSOR SIGNAL WITH A LAB SCOPE. Turn the ignition off.. With a lab scope probe and the Miller special tool 68, backprobe the (K44) CMP Signal circuit in the CMP harness connector.
WARNING:. Ignition on, engine not running. 4. Observe the lab scope screen. 5. Start the engine. 6. Observe the lab scope screen. When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts or fan. Do not wear loose clothing. Failure to follow these instructions may result in possible serious or fatal injury. Are there any irregular or missing signals? Yes Go To No Go To 8. WIRE HARNESS INSPECTION. Turn the ignition off.. Visually inspect the related wire harness including the ground circuit. Look for any chafed, pierced, pinched, or partially broken wires.. Verify that there is good pin to terminal contact in the CMP Sensor and Powertrain Control Module connectors. 4. Visually inspect the related wire harness connectors. Look for broken, bent, pushed out, or corroded terminals. 5. Make sure the Crankshaft Position Sensor and the Camshaft Position Sensor are properly installed and the mounting bolt(s) are torqued to the proper specification. 6. Refer to any TSBs that may apply. Were any of the above conditions present? Yes Repair as necessary. TEST. (Refer to 8 - DTC-Based Diagnostics/MODULE, No Go To 4
4. (F856) 5-VOLT SUPPLY CIRCUIT OPEN OR SHORTED TO GROUND. Disconnect the CMP Sensor connector.. Ignition on, engine not running.. Measure the voltage on the (F856) 5-Volt Supply circuit in the CMP harness connector. Is the voltage between 4.5 and 5. Volts? V Yes Go To 5 No Repair the open or short to ground in the (F856) 5-Volt Supply circuit. Use Miller PCM Pinout Box 885A when checking for an open circuit to prevent PCM harness connector terminal damage. TEST. (Refer to 8 - DTC-Based Diagnostics/ 9545 5. TONE WHEEL/PULSE RING INSPECTION. Turn the ignition off.. Carefully disconnect the Battery Ground cable.. Remove the Camshaft Position Sensor. 4. Inspect the Tone Wheel/Pulse Ring for damage, foreign material, or excessive movement. Were any problems found? Yes Repair or replace the Tone Wheel/Pulse Ring as necessary. TEST. (Refer to 8 - DTC-Based Diagnostics/MODULE, No Go To 6 6. CHECKING CRANKSHAFT SENSOR SIGNAL WITH A LAB SCOPE NOTE: An intermittent condition in the Crank Position Sensor can cause the P44 to set.. Install the CMP Sensor and connect the Battery cable.. With a lab scope probe and the Miller special tool 68, backprobe the (K4) CKP Signal circuit in the CKP harness connector. WARNING:. Ignition on, engine not running. When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts or fan. Do not wear loose clothing. Failure to follow these instructions may result in possible serious or fatal injury. 4. Wiggle the related wire harness and lightly tap on the Crank Position Sensor. 5. Observe the lab scope screen. 4
6. Start the engine. 7. Observe the lab scope screen. Are there any irregular or missing signals? Yes Verify that there is good pin to terminal contact in the CKP Sensor and Powertrain Control Module connectors. Replace the Crankshaft Position Sensor if no problems were found with the connectors. TEST. (Refer to 8 - DTC-Based Diagnostics/MODULE, No Go To 7 7. SENSOR If there are no possible causes remaining, view repair. Repair Verify that there is good pin to terminal contact in the CMP Sensor and Powertrain Control Module connectors. Replace the Camshaft Position Sensor if no problems were found with the connectors. TEST. (Refer to 8 - DTC-Based Diagnostics/MODULE, 8. (K44) CMP SIGNAL CIRCUIT SHORTED TO VOLTAGE. Turn the ignition off.. Disconnect the CMP Sensor connector.. Disconnect the C PCM harness connector. 4. Ignition on, engine not running. 5. Measure the voltage on the (K44) CMP Signal circuit. V 6. Wiggle the related wire harness while taking this measurement. Does the voltage ever increase above Volts? Yes Repair the short to voltage in the (K44) CMP Signal circuit. TEST. (Refer to 8 - DTC-Based Diagnostics/ No Go To 9 9547 5
9. (K44) CMP SIGNAL CIRCUIT OPEN. Turn the ignition off. CAUTION: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install the PCM Pinout Box 885A to perform diagnosis. C-4. Measure the resistance in the (K44) CMP Signal circuit from the CMP harness connector to the appropriate terminal of PCM Pinout Box 885A.. Wiggle the related wire harness while taking this measurement. Is the resistance below 5. Ohms? Yes Go To 9 6 4 PCM PINOUT BOX 885 8 5 8 No Repair the excessive resistance in the (K44) CMP Signal circuit. 954 TEST. (Refer to 8 - DTC-Based Diagnostics/. (K44) CMP SIGNAL CIRCUIT SHORTED TO GROUND. Measure the resistance between ground and the (K44) CMP Signal circuit in the CMP Sensor harness connector.. Wiggle the related wire harness while monitoring the resistance value. Does the resistance ever go below Ohms? Yes Repair the short to ground in the (K44) CMP Signal circuit. TEST. (Refer to 8 - DTC-Based Diagnostics/ No Go To 4985 6
. (K44) CMP SIGNAL CIRCUIT SHORTED TO THE (F856) 5-VOLT SUPPLY CIRCUIT. Measure the resistance between the (F856) 5-Volt Supply circuit and the (K44) CMP Signal circuit in the CMP harness connector.. Wiggle the related wire harness while taking this measurement. Is the resistance below 5. Ohms? Yes Repair the short between the (F856) 5-Volt Supply circuit and the (K44) CMP Signal circuit. TEST. (Refer to 8 - DTC-Based Diagnostics/ No Go To 954. POWERTRAIN CONTROL MODULE (PCM). Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the related Sensor and the Powertrain Control Module (PCM).. Look for any chafed, pierced, pinched, or partially broken wires.. Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the CMP Sensor and the Powertrain Control Module connectors. 4. Perform any Technical Service Bulletins that may apply. Were there any problems found? Yes Repair as necessary. TEST. (Refer to 8 - DTC-Based Diagnostics/MODULE, No Replace and program the Powertrain Control Module in accordance with the service information. TEST. (Refer to 8 - DTC-Based Diagnostics/MODULE, 7