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Lumbar Support Inoperative (A45)

  1. If lumbar support system check was performed, go to next step. If lumbar support system check was not performed, go to LUMBAR SUPPORT SYSTEM CHECK (A45)  under TROUBLE SHOOTING.
  2. Check the MEM T & T fuse (10-amp) in rear fuse block located under rear seat cushion. If fuse is open, go to next step. If fuse is okay, go to step  5 .
  3. Repair short to ground in Orange wire between lumbar switch and rear fuse block. See WIRING DIAGRAMS  . Go to next step.
  4. Replace MEM T & T fuse (10-amp). After replacement, go to LUMBAR SUPPORT SYSTEM CHECK (A45)  .
  5. Disconnect left lumbar switch Black, 7-pin connector. Using DVOM, measure voltage between ground and left lumbar switch connector terminal "G" (Orange wire). If 10-15 volts exists, go to next step. If 10-15 volts does not exist, go to step  10 .
  6. Using DVOM, measure voltage between left lumbar switch connector terminals "G" (Orange wire) and "E" (Black wire). If 10-15 volts exists, go to next step. If 10-15 volts does not exist, go to step  11 .
  7. If left lumbar moved when recalled on memory function switch during lumbar support system check, go to next step. If left lumbar did not move when recalled on memory function switch during lumbar support system check, go to step  9 .
  8. Replace left lumbar switch. See POWER SEATS - SEVILLE article. After repairs, recheck system operation.
  9. Replace Memory Seat Module (MSM). See MEMORY SEAT MODULE  under REMOVAL & INSTALLATION. After repairs, recheck system operation.
  10. Repair open in Orange wire between left seat switch and splice S326 located in left seat harness approximately 19" from forward/back position sensor. See WIRING DIAGRAMS  . After repairs, recheck system operation.
  11. Repair open in Black wire between Memory Seat Module (MSM) and splice S313 located in left seat harness approximately 20" from forward/back position sensor. See WIRING DIAGRAMS  . After repairs, recheck system operation.
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