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Test 12: Power Headrest Does Not Move Up/Down - With A45

  1. Perform POWER SEAT DIAGNOSTIC SYSTEM CHECK under SELF-DIAGNOSTIC SYSTEM in POWER SEATS - SEVILLE article. Go to next step.
  2. Install a scan tool. Turn ignition switch to ON position, engine off. Using scan tool, observe HEADREST UP parameter in MEMORY SEAT MODULE data list. Operate headrest switch in forward direction. If HEADREST UP parameter changes state, go to next step. If HEADREST UP parameter does not change state, go to step  5 .
  3. Using scan tool, observe HEADREST DOWN parameter. Operate headrest switch in backward direction. If HEADREST DOWN parameter changes state, go to next step. If HEADREST DOWN parameter does not change state, go to step  6 .
  4. Disconnect 2-pin seat recline motor connector. Connect a test light between seat recline motor connector terminals "A" (Yellow/Black wire) and "B" (Purple/Black wire). Operate headrest switch in forward and backward directions. If test light illuminates in both directions, go to step  13 . If test light does not illuminate in both directions, go to step  7 .
  5. Disconnect power seat switch connector. Using scan tool, observe HEADREST UP parameter. Connect fused jumper wire (3-amp) between battery voltage and seat switch connector terminal "K" (White/Black wire). See Figure . If HEADREST UP parameter changes state, go to step  12 . If HEADREST UP parameter does not change state, go to step  9 .
  6. Disconnect power seat switch connector. Using scan tool, observe HEADREST DOWN parameter. Connect fused jumper wire (3-amp) between battery voltage and seat switch connector terminal "M" (Dark Blue/White wire). See Figure . If HEADREST DOWN parameter changes state, go to step  12 . If HEADREST DOWN parameter does not change state, go to step  10 .
  7. Check Yellow/Black wire between Memory Seat Module (MSM) and headrest motor for short to ground or open. If problem is found, repair as necessary, then go to step  17 . If problem is not found, go to next step.
  8. Check Purple/Black wire between MSM and headrest motor for short to ground or open. If problem is found, repair as necessary, then go to step  17 . If problem is not found, go to step  11 .
  9. Check White/Black wire between power seat switch and MSM for open. If problem is found, repair as necessary, then go to step  17 . If problem is not found, go to step  11 .
  10. Check Dark Blue/White wire between power seat switch and MSM for open. If problem is found, repair as necessary, then go to step  17 . If problem is not found, go to next step.
  11. Check MSM connector for poor connections. If problem is found, repair as necessary, then go to step  17 . If problem is not found, go to step  14 .
  12. Check power seat switch connector for poor connections. If problem is found, repair as necessary, then go to step  17 . If problem is not found, go to step  15 .
  13. Check headrest motor connector for poor connections. If problem is found, repair as necessary, then go to step  17 . If problem is not found, go to step  16 .
  14. Replace MSM. See MEMORY SEAT MODULE  under REMOVAL & INSTALLATION. After repairs, go to step  17 .
  15. Replace power seat switch. See POWER SEAT SWITCHES under REMOVAL & INSTALLATION in POWER SEATS - SEVILLE article. After repairs, go to step  17 .
  16. Replace headrest motor. See SEAT MOTORS under REMOVAL & INSTALLATION in POWER SEATS - SEVILLE article. After repairs, go to next step.
  17. Operate system to verify repair. If system operates normally, repair is complete. If system does not operate normally, return to step  2 .
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