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DTC B1422: Device Power MODING Malfunction: Testing

  1. Perform BCM diagnostic system check. See BODY CONTROL MODULE (BCM) DIAGNOSTIC SYSTEM CHECK  under SELF-DIAGNOSTIC SYSTEM. After performing diagnostic system check, go to next step.
  2. Check CRANK SIGNAL, BCM, CLUSTER fuse (10-amp) in fuse block. If fuse is blown, go to next step. If fuse is not blown, go to step  4 .
  3. Turn ignition off. Replace fuse. Momentarily turn ignition switch to START position. Check fuse again. If fuse is blown again, go to step  13 . If fuse is okay, go to next step.
  4. Check IGN 0, CLUSTER, PCM and BCM fuse (10-amp) in fuse block. If fuse is blown, go to next step. If fuse is not blown, go to step  6 .
  5. Turn ignition off. Replace fuse. Momentarily turn ignition switch to ON position. Check fuse again. If fuse is blown again, go to step  14 . If fuse is okay, go to next step.
  6. Turn ignition off. Using a test light connected to ground, backprobe Blue BCM harness connector C1 terminal "J" (Pink wire). See WIRING DIAGRAMS  . If test light does not illuminate, go to next step. If test light illuminates, go to step  15 .
  7. With test light still connected as in step 6)  , observe test light. Turn ignition switch to RUN position and then to START position. Turn ignition off. If test light illuminated in both RUN and START positions, go to next step. If test light did not illuminate in both RUN and START positions, go to step  16 .
  8. Turn ignition off. Using a test light connected to ground, backprobe Black BCM harness connector C3 terminal B9 (Purple wire). See WIRING DIAGRAMS  . Turn ignition switch from OFF to ON position. If test light does not illuminate, go to next step. If test light illuminates, go to step  17 .
  9. With test light still connected as in step 8)  , observe test light. Turn ignition switch from OFF to START position momentarily. Turn ignition off. If test light illuminated in START position, go to next step. If test light did not illuminate in START position, go to step  18 .
  10. Ensure ignition is off. Using a test light connected to ground, backprobe Blue BCM harness connector C1 terminal "J" (Pink wire). See WIRING DIAGRAMS  . If test light does not illuminate, go to next step. If test light illuminates, go to step  19 .
  11. With test light still connected as in step 10)  , observe test light. Turn ignition switch to ACC position, then to RUN position, and then to START position. Turn ignition off. If test light illuminated in all 3 positions, go to next step. If test light did not illuminate in all 3 positions, go to step  20 .
  12. Using scan tool, clear BCM DTCs. Turn ignition off. Wait 10 seconds. Turn ignition on. Check for BCM DTCs. See BODY CONTROL MODULE (BCM) DIAGNOSTIC SYSTEM CHECK  under SELF-DIAGNOSTIC SYSTEM. If DTC B1422 is present as a current code, go to step  21 . If DTC B1422 is not present as a current code, go to step  22 .
  13. Repair short to ground in Purple wire between Black BCM connector C3 terminal B9 and fuse block. See WIRING DIAGRAMS  . After repair, go to step  23 .
  14. Repair short to ground in Purple wire between Black BCM connector C3 terminal B10 and fuse block. See WIRING DIAGRAMS  . After repair, go to step  23 .
  15. Repair short to voltage in Pink wire between Blue BCM connector C1 terminal "J" and fuse block. See WIRING DIAGRAMS  . After repair, go to step  23 .
  16. Repair poor connection or open in Pink wire between Blue BCM connector C1 terminal "J" and fuse block. See WIRING DIAGRAMS  . After repair, go to step  23 .
  17. Repair short to voltage in Purple wire between Black BCM connector C3 terminal B9 and fuse block or replace faulty ignition switch. See WIRING DIAGRAMS  . After repair, go to step  23 .
  18. Repair poor connection or open in Purple wire between Black BCM connector C3 terminal B9 and fuse block. See WIRING DIAGRAMS  . After repair, go to step  23 .
  19. Repair short to voltage in Purple wire between Black BCM connector C3 terminal B10 and fuse block or replace faulty ignition switch. See WIRING DIAGRAMS  . After repair, go to step  23 .
  20. Repair poor connection or open in Purple wire between Black BCM connector C3 terminal B10 and fuse block or replace faulty ignition switch. See WIRING DIAGRAMS  . After repair, go to step  23 .
  21. Check Blue BCM connector C1 for poor connections. If connections are okay, replace BCM. See BODY CONTROL MODULE (BCM)  under REMOVAL & INSTALLATION. CRANK voltage is greater than 4.5 volts and Ignition 1 voltage is less than 1.5 volts. After repair, go to step  23 .
  22. Malfunction is not present at this time. See DIAGNOSTIC AIDS  for more information. After repair, go to next step.
  23. Turn ignition off. Reinstall all disconnected components and harness connectors. Install scan tool. Turn ignition on. Using scan tool, clear BCM DTCs. Check for current BCM DTCs. See BODY CONTROL MODULE (BCM) DIAGNOSTIC SYSTEM CHECK  under SELF-DIAGNOSTIC SYSTEM. Repair as required. If no BCM DTCs are present as current codes, system is okay.
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