Test 3A: Loss Of Ignition Run-Start
WARNING: This page is about a different car, the 2002 Jeep Grand Cherokee. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:
Prior to performing any air bag system test, go to PRETEST INSPECTION & DIAGNOSTIC PROCEDURE
under DIAGNOSTICS. Perform TEST VER-1: AIR BAG VERIFICATION TEST
after all repairs unless otherwise directed.
Air Bag Control Module (ACM) harness connectors C1 and C2 are identical, except for wire colors and terminal usage. See WIRING DIAGRAMS .
Air Bag Control Module (ACM) harness connectors C1 and C2 are identical, except for wire colors and terminal usage. See WIRING DIAGRAMS .
- Turn ignition switch to ON position. Using DRBIII, determine which control module is generating Diagnostic Trouble Code (DTC). If LOSS OF IGNITION RUN-START is an active DTC, go to next step. If LOSS OF IGNITION RUN-START is a stored DTC, go to TEST 1B: REPAIRING STORED CODES .
- Turn ignition switch to OFF position. Remove air bag ignition run/start fuse No. 32 and check condition of fuse. See Figure . If fuse is bad, go to next step. If fuse is good, go to step 4 .
- Disable air bag system. See DISABLING SYSTEM under DISABLING & ACTIVATING AIR BAG SYSTEM. Connect ohmmeter to air bag system side of fuse No. 32 cavity and ground. While monitoring ohmmeter, disconnect air bag system components, one at a time. See REMOVAL & INSTALLATION . If resistance is more than 10 k/ohms after disconnecting a component, replace faulty component. If resistance is less than 10 k/ohms after all components are removed, repair short to ground in ignition run/start circuit. See WIRING DIAGRAMS .
- Turn ignition switch to ON position. Measure voltage between ground and ignition switch output side of fuse No. 32 cavity. If voltage is less than 4.5 volts, repair open in air bag ignition run/start circuit between battery and fuse holder. See WIRING DIAGRAMS . If voltage is more than 4.5 volts, go to next step.
- Disable air bag system. See DISABLING SYSTEM under DISABLING & ACTIVATING AIR BAG SYSTEM. Access ACM and disconnect harness connector C1. See AIR BAG CONTROL MODULE (ACM) under REMOVAL & INSTALLATION. Install run/start fuse No. 32. Turn ignition switch to ON position. Connect negative battery cable. Measure voltage between ground and ACM connector C1, terminal No. 24. (Light Green/Yellow wire). See Figure . If voltage is less than 4.5 volts, repair open or high resistance in Light Green/Yellow wire. If voltage is more than 4.5 volts, replace ACM.