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Test C: AUTOLOCK Does Not Operate Properly

WARNING: This page is about a different car, the 1998 Lincoln Navigator. However, it is still accessible from the selected car via links, so may be relevant.
  1. Ensure autolock and relock features operate as described in owners manual. If autolock operates as specified, no problem is indicated at this time. If autolock does not operate as specified, go to next step.
  2. Connect NGS tester following manufacturer's instructions. Retrieve continuous DTCs. Clear DTCs. Perform RAP on-demand self test. If no DTCs are retrieved, go to step 9). If DTC B1485 is retrieved, go to next step. If DTC 1629 is retrieved, go to step 6). If any other DTCs are retrieved, go to step 9).
  3. Turn ignition on. Select PID BOO_RAP to monitor BRAKE ON/OFF switch. Ensure display shows ON. If display shows ON, go to step 6). If display does not show ON, go to next step.
  4. Select PID BOO_RAP to monitor BRAKE ON/OFF switch. Ensure display shows ON and OFF state as brake pedal is pressed and released. If operation is as specified, clear DTCs. Perform on-demand self-test. If DTC B1485 is retrieved, replace RAP module. Retest system. If display does not change from OFF to ON to OFF, go to next step.
  5. Turn ignition off. Disconnect RAP module 26-pin connector C256. Turn ignition on. Measure voltage between ground and RAP module 26-pin connector C256 terminal No. 26 (Light Green wire). See Figure . If any voltage is present, repair short to power in Light Green wire. Retest system. If no voltage is indicated, replace RAP module. Retest system.
  6. Turn ignition off. Select PID TRANSGR to monitor transmission range switch. If display shows REV, go to step 8). If display does not show REV, go to next step.
  7. Select PID TRANSGR while moving gear selector lever from P to R to P. If display changes from notREV, to REV, to notREV, clear DTCs. Perform on-demand self-test. If DTC B1629 is retrieved, replace RAP module. Retest system. If display does not change as specified, go to next step.
  8. Turn ignition off. Disconnect RAP module 26-pin connector C256. Measure voltage between ground and RAP module 26-pin connector C256 terminal No. 12 (Black/Pink wire). If any voltage is present, repair short to power in Black/Pink wire. Retest system. If no voltage is present, replace RAP module. Retest system.
  9. Select PID BOO_RAP to monitor BRAKE ON/OFF switch. Ensure display shows OFF to ON to OFF as brake pedal is pressed and released. If operation is as specified, go to step 12). If display always shows ON, go back to step 5). If display always shows OFF, go to next step.
  10. 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.
  11. Turn ignition off. Disconnect RAP module 26-pin connector C256. Turn ignition on. Press down and hold brake pedal. Measure voltage between ground and RAP module 26-pin connector C256 terminal No. 26 (Light Green wire). If voltage less than 10 volts, repair Light Green wire. Retest system. If voltage is more than 10 volts, replace RAP module. Retest system.
  12. 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 15). If display always shows REV, go back to step 8). If display always shows notREV, go to next step.
  13. Turn ignition on. Turn headlights on. Place gear selector lever in Reverse. If back-up lights come on, go to next step. If back-up lights do not come on, repair back-up light circuit. Retest system.
  14. Turn ignition off. Disconnect RAP module 26-pin connector C256. Turn ignition on. Place gear selector lever in Reverse. Measure voltage between ground and RAP module 26-pin connector C256 terminal No. 12 (Black/Pink wire). If any voltage is present, replace RAP module. Retest system. If no voltage is present, repair Black/Pink wire. Retest system.
  15. Connect NGS tester. Retrieve continuous DTCs. Clear DTCs. Perform RAP on-demand self test with all doors closed. If no DTCs are retrieved, go to next step. If DTCs B1322, B1330, B1332, B1338 or B1574 are retrieved, problem is in interior lighting system. See appropriate wiring diagram in ILLUMINATION/INTERIOR LIGHTS article.
  16. Turn ignition on. Select PID DOORRAP. Close all doors. Display should read CLOSED. Open any door. Display should read AJAR. If display reads as specified, go to step 19). If display always reads AJAR, go to next step. If PID display always reads CLOSED, go to step 18).
  17. Turn ignition off. Disconnect RAP module 26-pin connector C256. Disconnect GEM 18-pin connector C240. Measure resistance between ground and RAP module 26-pin connector C256 terminal No. 11 (Light Blue/White wire). If resistance is more than 10 k/ohms, replace RAP module. Retest system. If resistance is less than 10 k/ohms, repair short to ground in Light Blue/White wire. Retest system.
  18. Measure resistance between ground and RAP module 26-pin connector C256 terminal No. 11 (Light Blue/White wire). If resistance is less than 1000 ohms, replace RAP module. Retest system. If resistance is more than 1000 ohms, repair Light Blue/White wire. Retest system.
  19. Turn ignition on. Select PID IGN_RAP. Turn ignition to RUN position, then back to off. If PID changes from OFF to RUN/ACC to OFF, all system inputs are okay. If display always reads RUN/ACC, go to next step. If display always reads OFF, go to step 22).
  20. Turn ignition off. Disconnect RAP module 26-pin connector C256. Measure voltage between ground and RAP module 26-pin connector C256 terminal No. 25 (Black/Pink wire). If any voltage is present, repair short to power in Black/Pink wire. Retest system. If no voltage is present, replace RAP module. Retest system.
  21. Turn ignition on. Measure voltage between ground and RAP module 26-pin connector C256 terminal No. 25 (Black/Pink wire). If voltage is less than 10 volts, repair Black/Pink wire. Retest system. If voltage is more than 10 volts, replace RAP module. Retest system.
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