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Test D: Key-In-Ignition Circuit

  1. Remove fuse No. 28 (15-amp) from Central Junction Box (CJB). CJB is located behind left side of instrument panel. 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 CJB. See appropriate wiring diagram in POWER DISTRIBUTION article in WIRING DIAGRAMS.
  2. Remove fuse No. 32 (15-amp) from CJB. 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 CJB. See appropriate wiring diagram in POWER DISTRIBUTION article in WIRING DIAGRAMS.
  3. Turn ignition switch to LOCK position. Disconnect GEM 26-pin harness connector C352. Ensure fuse No. 28 is removed from CJB. Measure resistance in White/Light Green wire between GEM harness connector C352 terminal No. 8 and output side of fuse No. 28 in CJB. See Figure . If resistance is 5 ohms or less, go to next step. If resistance is more than 5 ohms, repair open in White/Light Green wire between GEM and fuse No. 28. See appropriate wiring diagram in POWER DISTRIBUTION article in WIRING DIAGRAMS.
  4. Ensure fuse No. 32 is removed from CJB. Measure resistance in Black/Pink wire between GEM harness connector C352 terminal No. 22 and output of fuse No. 32 in CJB. If resistance is 5 ohms or less, go to next step. If resistance is more than 5 ohms, repair open in Black/Pink wire between GEM and fuse No. 32. See appropriate wiring diagram in POWER DISTRIBUTION article in WIRING DIAGRAMS.
  5. Measure resistance between ground and GEM harness connector C352 terminal No. 9 (Black/Pink wire). If resistance is 5 ohms or less, go to next step. If resistance is more than 5 ohms, check for open in Black/Pink wire between GEM and key-in-ignition warning switch. See WIRING DIAGRAMS  . Repair as necessary. If Black/Pink wire is okay, replace key-in-ignition warning switch. See REMOVAL & INSTALLATION  .
  6. Remove ignition key. Measure voltage between ground and GEM harness connector C352 terminal No. 8 (White/Light Green wire). Measure voltage between ground and GEM harness connector C352 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). See WIRING DIAGRAMS  .
  7. Measure resistance between ground and GEM harness connector C352 terminal No. 9 (Black/Pink wire). 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. See WIRING DIAGRAMS  .
  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 REMOVAL & INSTALLATION  . If problem no longer exists, system is operating correctly at this time.
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