Starting System - Electrical Diagnostics Jeep Grand Cherokee WK

Scheme 42

Additional Wiring

For complete wiring diagrams, refer to SYSTEM WIRING DIAGRAMS article.

Monitor Conditions

1. When Monitored: Continuously

Set Conditions

1. Set Condition: When the FCM senses 12 volts on the Hood Ajar Switch Sense circuit for over 10 seconds, this code will set.

Possible Causes

Scheme 43

Scheme 44

Scheme 45

Scheme 46

1. 1) TEST FOR INTERMITTENT CONDITION NOTE: Open the hood and ensure the Hood Ajar Switch is connected before proceeding With the scan tool, record and erase DTC's Close the hood. Cycle the ignition from on to off. Turn the ignition on. Open then close the hood. With the scan tool, read DTC's. Does the scan tool display B1820-HOOD AJAR INPUT CIRCUIT HIGH? Yes Go To step 2) . No The conditions that caused this code to set are not present at this time. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors. Perform «BODY VERIFICATION TEST - VER 1»(/jeep/grand-cherokee/wk-2004-2010/remont/communication-devices/#electronic-control-modules-electrical-diagnostics) .
2. 2) INCORRECT HOOD AJAR SWITCH INSTALLED Inspect the retainer ring on the hood ajar switch. A dark brown retainer ring identifies the hood ajar switch used for certain export applications, while a white retainer ring identifies the remote starter system application. Is the correct switch installed? Yes Go To step 3) . No Replace the Hood Ajar Switch. Perform «BODY VERIFICATION TEST - VER 1»(/jeep/grand-cherokee/wk-2004-2010/remont/communication-devices/#electronic-control-modules-electrical-diagnostics) .
3. 3) HOOD AJAR SWITCH OPEN Disconnect the Hood Ajar Switch harness connector. Measure the resistance between the two terminals of the Hood Ajar Switch Is the resistance approximately 1000 ohms? Yes Go To step 4) . No Replace the Hood Ajar Switch. Perform «BODY VERIFICATION TEST - VER 1»(/jeep/grand-cherokee/wk-2004-2010/remont/communication-devices/#electronic-control-modules-electrical-diagnostics) .
4. 4) (Z384) GROUND CIRCUIT OPEN Using a 12-volt Test Light connected to 12-volts, check the (Z384) Ground circuit. Does the test light illuminate? Yes Go To step 5) . No Repair the (Z384) Ground circuit for an open. Perform «BODY VERIFICATION TEST - VER 1»(/jeep/grand-cherokee/wk-2004-2010/remont/communication-devices/#electronic-control-modules-electrical-diagnostics) .
5. 5) (G70) HOOD AJAR SWITCH SENSE CIRCUIT SHORT TO VOLTAGE Disconnect the Front Control Module 49-way connector. Turn the ignition on. Measure the voltage between the (G70) Hood Ajar Switch Sense circuit and ground. Is there any voltage present? Yes Repair the (G70) Hood Ajar Switch Sense circuit for a short to voltage. Perform «BODY VERIFICATION TEST - VER 1»(/jeep/grand-cherokee/wk-2004-2010/remont/communication-devices/#electronic-control-modules-electrical-diagnostics) . No Go To step 6) .
6. 6) (G70) HOOD AJAR SWITCH SENSE CIRCUIT OPEN Turn the ignition off. Disconnect the Integrated Power Module C2 40-way connector. Measure the resistance of the (G70) Hood Ajar Switch Sense circuit between the IPM connector and the Hood Ajar Switch connector. Is the resistance below 2.0 ohms? Yes Go To step 7) . Perform «BODY VERIFICATION TEST - VER 1»(/jeep/grand-cherokee/wk-2004-2010/remont/communication-devices/#electronic-control-modules-electrical-diagnostics) . No Repair the (G70) Hood Ajar Switch Sense circuit for an open. Perform «BODY VERIFICATION TEST - VER 1»(/jeep/grand-cherokee/wk-2004-2010/remont/communication-devices/#electronic-control-modules-electrical-diagnostics) .
7. 7) (G70) IPM HOOD AJAR SWITCH SENSE CIRCUIT OPEN NOTE: Use the graphic connector pinout as a reference to check the Integrated Power Module. Measure the resistance of the (G70) Hood Ajar Switch Sense circuit between the IPM C2 40-connector and the Front Control Module 49-way connector. Is the resistance below 1.0 ohms? Yes Replace the Front Control Module (FCM) in accordance with the service information. Perform «BODY VERIFICATION TEST - VER 1»(/jeep/grand-cherokee/wk-2004-2010/remont/communication-devices/#electronic-control-modules-electrical-diagnostics) . No Replace the Integrated Power Module (IPM) in accordance with the service information. Perform «BODY VERIFICATION TEST - VER 1»(/jeep/grand-cherokee/wk-2004-2010/remont/communication-devices/#electronic-control-modules-electrical-diagnostics) .

For complete wiring diagrams, refer to SYSTEM WIRING DIAGRAMS article.

Theory Of Operation

The customer may notice that the signal range of the Remote Keyless Entry (RKE) system is reduced. The RKE key fob may need to be closer than 3 meters (10 feet) before the functions available on the key fob will operate. This condition may be due to the RKE antenna. The diagnostic flow chart is provide as a diagnostic aid for dealer technician.

Diagnostic Test

1. 1) LOCK/UNLOCK FUNCTION NOTE: For all RKE tests, the key must be out of the ignition. Does the Lock/Unlock function with the interior door switches? Yes Go To step 2) . No Perform Power Lock/Unlock System diagnosis.
2. 2) RKE FUNCTION AT 20 FEET Does the RKE Function at 20 feet? Yes Go To step 3) . No Go To step 4) .
3. 3) RKE FUNCTION AT 100 FEET Does the RKE Function at 100 feet? Yes Test complete. No Replace the antenna in accordance with the service information.
4. 4) WCM DTCS Does the WCM display any DTCs? Yes Perform WCM diagnosis. No Go To step 5) .
5. 5) RKE FUNCTION INSIDE VEHICLE Sit inside the vehicle. Push the Key Fob RKE Lock/Unlock buttons. Does the RKE Lock/Unlock work? Yes Go To step 6) . No Go To step 9) .
6. 6) ANTENNA COAX CABLE NOT PROPERLY CONNECTED Pull on the Antenna COAX cable connector at the WCM. Did the connector come off without releasing the lock tab (not properly seated)? Yes Connect Antenna Go To step 2) . No Go To step 7) .
7. 7) VERIFY COAX CONNECTION AT WCM Pull Antenna connector off WCM. Verify no bent pins. Are there any bent pins? Yes Replace antenna. Go To step 2) . No Go To step 8) .
8. 8) PINCHED WIRE Inspect the ANTENNA Lead COAX Cable for a pinched wire. Has the COAX cable been pinched or damaged? Yes Replace antenna. Go To step 2) . No Perform WCM diagnostics.
9. 9) RKE FUNCTION INSIDE VEHICLE Disconnect the Antenna COAX Cable lead connector to WCM. Sit inside the vehicle. Push the RKE Key Fob Lock/Unlock buttons. Does the RKE Lock/Unlock work? Yes Replace the antenna. No Go To step 10) .
10. 10) CHECK FOR 12 VOLTS AT WCM Connect the Antenna Lead to WCM. Disconnect the WCM harness connector. Using the appropriate wiring diagrams, check for Fused B+ at the WCM harness connector. Is Fused B+ present? Yes Perform WCM diagnostics. No Repair the appropriate circuits.

For complete wiring diagrams, refer to SYSTEM WIRING DIAGRAMS article.

1. 1) REMOTE START PARAMETERS NOT MET / FAULTY COMPONENT Refer to the Data Display in the scan tool to view possible causes of the inoperative Remote Start System. Repair See the following list for possible causes for the inoperative Remote Start System: ABORT BATTERY VOLTAGE HIGH BATTERY VOLTAGE LOW BRAKE PRESSED COOLANT TEMPERATURE HIGH CRANK NO START DRIVER DOOR AJAR EXCESSIVE GLOW PLUG TIME (DIESEL ONLY) FAILED COUNTER REACHED (START) HAZARD LAMPS (SWITCH PRESSED) HOOD AJAR IGNITION IN RUN/START IGNITION NOT IN LOCK IGNITION SNA (SIGNAL NOT AVAILABLE FROM OTHER MODULE) INVALID KEY KEY IN IGNITION LEFT REAR DOOR AJAR LOW RPM SHUTDOWN MIL ON NO AUTOMATIC TRANSMISSION NO HOOD SWITCH (INOPERATIVE) NORMAL TIME OUT CUSTOMER ACCESS NORMAL TIME OUT RUN MODE (15 MINUTES) NOT CONFIGURED NOT ENABLED NOT IN PARK OR NEUTRAL NOT PROGRAMMED OIL PRESSURE LOW PANIC MODE (ACTIVATED) PASSENGER DOOR AJAR POWER LOSS RIGHT REAR DOOR AJAR RKE OFF MESSAGE RPM TOO HIGH (EXCEEDS 2500) START COUNTER REACHED TRUNK/LIFTGATE AJAR VEHICLE SPEED HIGH VTA ALARMING If all of the previous items checked OK, and the remote starting system will not operate, refer to «*REMOTE START INOPERATIVE-ANTENNA»(/jeep/grand-cherokee/wk-2004-2010/remont/charging-system/#starting-system-electrical-diagnostics) for further information. Refer to «DIAGNOSIS AND TESTING»(/jeep/grand-cherokee/wk-2004-2010/remont/starter/#starting-system-service-information) .

See also:
• BODY VERIFICATION TEST - VER 1
• DIAGNOSIS AND TESTING
• *REMOTE START INOPERATIVE-ANTENNA