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Test B: AUTOLOCK Does Not Operate Properly

  1. Ensure autolock and relock features operate as described in DESCRIPTION & OPERATION. If autolock operates as specified, no problem is indicated at this time. If autolock does not operate as specified, go to next step.
  2. Perform enable/disable sequence for autolock/relock feature as described in AUTOLOCK ENABLE/DISABLE under PROGRAMMING. If horn chirps once and is followed by a longer honk, autolock is now enabled. Repeat step 1)  . If only one horn chirp is heard, autolock has been disabled. Repeat step to enable. Go to next step.
  3. Connect NGS tester following manufacturers instructions. Retrieve continuous DTCs. Clear DTCs. Perform RAP on-demand self test. If no DTCs are retrieved, go to next step. If DTC B1485 is retrieved, go to next step. If DTC 1629 is retrieved, go to step  8 .
  4. Turn ignition switch to RUN position. Monitor RAP PID BOO_RAP. If display shows ON, go to step  7 . If display does not show ON, go to next step.
  5. Turn ignition switch to RUN position. Monitor RAP PID BOO_RAP. Ensure display shows ON and OFF state as brake pedal is pressed and released. If operation is as specified, clear DTCs. Perform RAP on-demand self test. If no DTCs are retrieved, go to next step. If DTC B1485 is retrieved, replace RAP module. Clear DTCs. Retest system.
  6. Turn ignition off. Disconnect RAP module 26-pin connector C256. Measure voltage between ground and RAP module 26-pin connector C256 terminal No. 26 (Light Green wire). See Figure . If any voltage exists, repair short to power in Light Green wire. Retest system. If no voltage exists, replace RAP module. Clear DTCs. Retest system.
  7. Turn ignition switch to RUN position. Using NGS tester, monitor RAP PID TRANSGR. If display shows REV, go to step  9 . If display does not show REV, go to next step.
  8. Monitor RAP PID TRANSGR while moving gear selector lever from Park to Reverse to Park. If display shows REV while shift lever is in reverse position, clear DTCs. Perform RAP on-demand self test. If no DTCs are retrieved, go to next step. If DTC B1629 is retrieved, replace RAP module. Clear DTCs. Retest system. If display does not shows REV while shift lever is in reverse position, go to next step.
  9. Turn ignition off. Disconnect RAP module 26-pin connector C256. Measure voltage between ground and RAP module connector C256 terminal No. 12 (Black/Pink wire). See Figure . If more than 10 volts exists, repair Black/Pink wire. Retest system. If 10 volts or less exists, replace RAP module. Clear DTCs. Retest system.
  10. Turn ignition switch to RUN position. Monitor RAP PID BOO_RAP. Ensure display shows ON and OFF state as brake pedal is pressed and released. If operation is as specified, go to step 13). If display shows always ON, go to step  6 . If PID display shows always OFF, go to next step.
  11. Depress brake pedal to check operation of brakelights. If brakelights operate, go to next step. If brakelights do not operate, repair brakelights, then retest system.
  12. Turn ignition off. Disconnect RAP module 26-pin connector C256. Turn ignition switch to RUN position. Depress brake pedal and hold. Measure voltage between ground and RAP module connector C256 terminal No. 26 (Red/Light Green wire). If more than 10 volts exists, replace RAP module. Clear DTCs. Retest system. If 10 volts or less exists, repair open in Red/Light Green wire. Clear DTCs. Retest system.
  13. Connect NGS tester. Select PID TRANSGR while moving gear selector lever from Park to Reverse to Park. If display changes from notREV, to REV, to notREV, go to step  16 . If display always shows REV, go back to step  9 . If display always shows notREV, go to next step.
  14. Turn ignition on. Place gear selector lever in Reverse. If back-up lights illuminate, go to next step. If back-up lights do not illuminate, see appropriate wiring diagram in ILLUMINATION/INTERIOR LIGHTS article.
  15. Turn ignition off. Disconnect RAP module 26-pin connector C256. Turn ignition switch to RUN position. Measure voltage between ground and RAP module 26-pin connector C256 terminal No. 12 (Black/Pink wire). See Figure . If any voltage exists, replace RAP module. Clear DTCs. Retest system. Clear DTCs. Retest system. If no voltage exists, repair Black/Pink wire.
  16. Connect NGS tester. Retrieve continuous DTCs. Clear DTCs. Perform GEM on-demand self test with all doors closed. If no DTCs are retrieved, go to next step. If DTCs B1322, B1330, B1332or B1574 are retrieved, problem is in interior lighting system. See appropriate wiring diagram in ILLUMINATION/INTERIOR LIGHTS article.
  17. Turn ignition on. Monitor RAP PID DOORRAP. Close all doors. Display should read CLOSED. Open any door. Display should read AJAR. If display reads as specified, go to step  13 . If display always reads AJAR, go to next step. If PID display always reads CLOSED, go to step  12 .
  18. Turn ignition off. Disconnect RAP module 26-pin connector C256. Disconnect GEM 18-pin connector C240. Measure resistance between ground and RAP module connector C256 terminal No. 11 (Light Blue/White wire). See Figure . If resistance is more than 10 k/ohms, replace RAP module. Clear DTCs. Retest system. If resistance is less than 10 k/ohms, repair short to ground in Light Blue/White wire. Clear DTCs. Retest system.
  19. Turn ignition off. Disconnect RAP module 26-pin connector C256. Open driver's door. Measure resistance between ground and RAP module 26-pin connector C256 terminal No. 11 (Light Blue/White wire). See Figure . If resistance is less than 1000 ohms, replace RAP module. Clear DTCs. Retest system. If resistance is more than 1000 ohms, repair open in Light Blue/White wire. Retest system.
  20. Turn ignition off. Select RAP PID IGN_RAP. Turn ignition switch to RUN position, then back to OFF. If PID changes from OFF to RUN to OFF, all system inputs are okay at this time. Verify customer complaint, go to SYMPTOM INDEX  table. If display always reads RUN, go to next step. If display always reads OFF, go to step  22 .
  21. Turn ignition off. Disconnect RAP module 26-pin connector C256. Measure voltage between ground and RAP module connector C256 terminal No. 25 (Black/Pink wire). See Figure . If 10 volts or less exists, repair open in Black/Pink wire. Retest system. If more than 10 volts exists, replace RAP module. Clear DTCs. Retest system.
  22. Turn ignition off. Disconnect RAP module 26-pin connector C256. Measure voltage between ground and RAP module connector C256 terminal No. 25 (Black/Pink wire). See Figure . If 10 volts or less exists, repair open in Black/Pink wire. Retest system. If more than 10 volts exists, replace RAP module. Clear DTCs. Retest system.
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