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Test D: Key-In-Ignition Circuit

NOTE: Perform all voltage and resistance tests using a Digital Volt-Ohm Meter (DVOM) with a minimum 10-megohm input impedance, unless stated otherwise in test procedure. Use ohmmeter to isolate wiring harness shorts or opens.
  1. Remove fuse No. 28 (15-amp) from Central Junction Box (CJB). CJB is located behind left side of instrument panel. See Figure. Measure voltage between ground and input side of fuse No. 28 while turning ignition switch through all positions. Battery voltage should exist in RUN and START positions only. If voltage is as specified, go to next step. If voltage is not as specified, repair or replace power supply circuit to CJB. For POWER DISTRIBUTION circuit identification, see WIRING DIAGRAMS . After repair, test system for normal operation.
  2. Remove fuse No. 32 (15-amp) from Central Junction Box (CJB). CJB is located behind left side of instrument panel. See Figure. Measure voltage between ground and input side of fuse No. 32 while turning ignition switch through all positions. Battery voltage should exist in RUN and ACC positions only. If voltage is as specified, go to next step. If voltage is not as specified, repair or replace power supply circuit to CJB. For POWER DISTRIBUTION circuit identification, see WIRING DIAGRAMS . After repair, test system for normal operation.
  3. Turn ignition switch to LOCK position. Disconnect GEM 26-pin harness connector C201e. See Figure. Ensure fuse No. 28 is removed from CJB. Measure resistance between GEM harness connector C201e terminal No. 8 and output side of fuse No. 28 in CJB (White/Light Green wire). If resistance is 5 ohms or less, go to next step. If resistance is more than 5 ohms, repair open circuit in White/Light Green wire between GEM and fuse No. 28. For POWER DISTRIBUTION circuit identification, see WIRING DIAGRAMS . After repair, test system for normal operation.
  4. Ensure fuse No. 32 is removed from CJB. Measure resistance between GEM harness connector C201e terminal No. 22 and output of fuse No. 32 in CJB (Black/Pink wire). If resistance is 5 ohms or less, go to next step. If resistance is more than 5 ohms, repair open circuit in Black/Pink wire between GEM and fuse No. 32. For POWER DISTRIBUTION circuit identification. See WIRING DIAGRAMS . After repair, test system for normal operation.
  5. Measure resistance between ground and GEM harness connector C201e terminal No. 9 (Black/Pink wire). See Figure. If resistance is 5 ohms or less, go to next step. If resistance is more than 5 ohms, check for open circuit in Black/Pink wire between GEM and key-in-ignition warning switch. For WARNING SYSTEMS circuit identification, see WIRING DIAGRAMS . If Black/Pink wire is okay, replace key-in-ignition warning switch. See KEY-IN-IGNITION WARNING SWITCH  under REMOVAL & INSTALLATION. After repair, test system for normal operation.
  6. Remove ignition key. Measure voltage between ground and GEM harness connector C201e terminal No. 8 (White/Light Green wire). See Figure. Also measure voltage between ground and GEM harness connector C201e terminal No. 22 (Black/Pink wire). If battery voltage does not exist on both circuits, go to next step. If battery voltage exists on either circuit, repair short to voltage in appropriate wire(s). For WARNING SYSTEMS circuit identification, see WIRING DIAGRAMS . After repair, test system for normal operation.
  7. Measure resistance between ground and GEM harness connector C201e terminal No. 9 (Black/Pink wire). See Figure. If resistance is more than 10 k/ohms, go to next step. If resistance is 10 k/ohms or less, repair short to ground in Black/Pink wire between GEM and key-in-ignition warning switch. For WARNING SYSTEMS circuit identification, see WIRING DIAGRAMS . After repair, test system for normal operation.
  8. Check for loose, damaged or corroded terminals in related circuits. Turn ignition switch to LOCK position. Reconnect all disconnected connectors and reinstall all components. Operate system. If problem still exists, replace GEM. See GENERIC ELECTRONIC MODULE  under REMOVAL & INSTALLATION. If problem no longer exists, system is operating correctly at this time. After repair, clear DTCs, repeat self-test and check system for normal operation.
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