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DTC B1805: Ignition Switch Problem: Testing

  1. If body control system diagnostic check has been performed, go to next step. If body control system diagnostic check has not been performed, perform body control system diagnostic check. See BODY CONTROL SYSTEM DIAGNOSTIC CHECK  under SYSTEM TESTS.
  2. Turn ignition switch to ON position. Using scan tool, clear DTCs. Turn ignition switch OFF and back to ON position. Recheck for DTCs. If this DTC resets, go to next step. If this DTC does not reset, go to step  21 .
  3. Turn ignition switch to ON position. Using scan tool, select DIM, then select INPUT MENU, then check inputs ON, ACC, UNLOCK and CRANK. If scan tool indicates that each input is active (corresponds to ignition switch position), go to step  20 . If scan tool does not indicate that each input is active, go to next step.
  4. Turn ignition switch to OFF position. Disconnect DIM connector C1. Using DVOM, measure voltage between ground and DIM connector terminal A3 (Pink wire). See WIRING DIAGRAMS  . See Figure . Turn ignition switch to ON, then to START position. If battery voltage is present in ON and START positions, go to step  7 . If battery voltage is not present in ON and START positions, go to next step.
  5. Check Pink wire for open or short to ground. If circuit is faulty, go to next step. If circuit is okay, go to step  19 .
  6. Repair Pink wire circuit. After repairs, go to step  21 .
  7. Using DVOM, measure voltage between ground and DIM connector terminal A2 (Brown wire). Turn ignition switch ON, then to ACC position. If battery voltage is present in ON and ACC positions, go to step  10 . If battery voltage is not present in ON and ACC positions, go to next step.
  8. Check for open or short in Brown wire. If circuit is faulty, go to next step. If circuit is okay, go to step  19 .
  9. Repair open or short in Brown wire. After repairs, go to step  21 .
  10. Using DVOM to measure voltage between ground and DIM connector terminal B2 (Yellow wire). Turn ignition switch to START position. If battery voltage is present in START position, go to step  13 . If battery voltage is not present in START position, go to next step.
  11. Check for open or short in Yellow wire. If circuit is faulty, go to next step. If circuit is okay, go to step  19 .
  12. Repair Yellow wire. After repairs, go to step  21 .
  13. Using DVOM to measure voltage between ground and DIM connector terminal B1 (Orange wire). Turn ignition switch to ON position. If battery voltage is present in ON position, go to step  16 . If battery voltage is not present in ON position, go to next step.
  14. Check for open or short to ground in Orange wire. If circuit is faulty, go to next step. If circuit is okay, go to step  19 .
  15. Repair Orange wire. After repairs, go to step  21 .
  16. Using DVOM to measure voltage between ground and DIM connector terminal A1 (White wire). Turn ignition switch to ACC, START, then ON position. If battery voltage is present in START, ON and ACC positions, go to step  20 . If battery voltage is not present in START, ON and ACC positions, go to next step.
  17. Check for open or short to ground in White wire. If circuit is faulty, go to next step. If circuit is okay, go to step  19 .
  18. Repair open or short to ground in White wire. After repairs, go to step  21 .
  19. Check for poor terminal contact at ignition switch connector. Repair as necessary. If terminal connector is okay, replace ignition switch. After repairs, go to step  21 .
  20. Check for poor terminal contact at DIM connector. Repair as necessary. If terminal contact is okay, replace DIM. See DASH INTEGRATION MODULE (DIM)  under REMOVAL & INSTALLATION. Program DIM. See DASH INTEGRATION MODULE (DIM)  under PROGRAMMING. After programming DIM, go to next step.
  21. Reconnect all components and connectors. Turn ignition switch to ON position. Using scan tool, clear DTCs. After clearing DTCs, perform body control system diagnostic check. See BODY CONTROL SYSTEM DIAGNOSTIC CHECK  under SYSTEM TESTS.
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