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Diagnostic Procedure

  1. Insert ignition key into Interrogator Adapter Harness (J-35628-A) to check vehicle key code number. If valid key code exists (No. 1-15), go to next step. If valid key code does not exist, replace ignition key. See REPLACING IGNITION KEY  under PROGRAMMING. Go to step  7 .
  2. Turn ignition switch to OFF position. Disconnect lock cylinder connector. Turn ignition switch to RUN position. Using a DVOM, measure voltage between terminals "A" and "B" of connector. See WIRING DIAGRAMS  . If voltage is not 4-6 volts, go to next step. If voltage is 4-6 volts, go to step  5 .
  3. Using a DVOM, measure voltage between lock cylinder connector terminal "A" and ground. If voltage is 4-6 volts, go to step  10 . If voltage is not 4-6 volts, go to step  8 .
  4. Turn ignition switch to OFF position. Reinstall any connectors or components that were removed. Turn ignition switch to RUN position. Clear DTCs. Check BCM for DTCs. If DTC does not reset, system is okay. If DTC resets, go to step  6 .
  5. Replace ignition lock cylinder. See appropriate STEERING COLUMN SWITCHES article. Go to step  4 .
  6. Replace BCM. See appropriate BODY CONTROL MODULES article. Go to next step.
  7. Turn ignition switch to OFF position. Reinstall any connectors or components that were removed. Turn ignition switch to RUN position. Clear DTCs. Check BCM for DTCs. If no BCM DTCs reset, system is okay. If any DTCs reset, see appropriate BODY CONTROL MODULES article.
  8. Disconnect BCM connector C1. Using DVOM, measure voltage between lock cylinder connector terminal "A" and ground. If voltage is less than 2 volts, go to step  9 . If voltage is 2 volts or more, repair short to battery voltage in White/Black wire between lock cylinder connector and BCM connector. See WIRING DIAGRAMS  . Go to step  7 .
  9. Using a DVOM, measure resistance in White/Black wire between lock cylinder connector terminal "A" and BCM connector C2 terminal B3. See Figure . If resistance is less than 2 ohms, go to step  4 . If resistance is 2 ohms or more, repair open or poor connection in White/Black wire. See WIRING DIAGRAMS  . Go to step  7 .
  10. Using a DVOM, measure voltage in Purple/White wire between lock cylinder connector terminal "B" and ground. If voltage is less than 2 volts, go to step  11 . If voltage is more than 2 volts, repair short to battery voltage in Purple/White wire. See WIRING DIAGRAMS  . Go to step  7 .
  11. Using a DVOM, measure resistance in Purple/White wire between lock cylinder connector terminal "B" and BCM connector C2 terminal B4. See Figure . If resistance is less than 2 ohms, go to step  4 . If resistance is 2 ohms or more, repair open or poor connection in Purple/White wire. See WIRING DIAGRAMS  . Go to step  7 .
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