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All Seat Functions Inoperative

  1. Using DVOM, check POWER SEATS circuit breaker (SEATS circuit breaker on Grand Prix) for an open. If circuit breaker is open, go to next step. If circuit breaker is okay, go to step 3)  .
  2. Check for short to ground in Orange wire between instrument panel fuse block and seat adjuster switch connector terminal "A". See WIRING DIAGRAMS  . If short is found, repair Orange wire, connector or fuse block as necessary. If circuit is okay, replace circuit breaker.
  3. Using test light connected to ground, backprobe power seat switch connector terminal "A" (Orange wire). See Fig 1 . If test light comes on, go to next step. If test light does not come on, go to step 5)  .
  4. Using test light, backprobe between power seat switch connector terminals "A" (Orange wire) and "D" (Black wire). If test light comes on, go to step 6)  . If test light does not come on, go to step 9)  .
  5. Repair poor connection or open in Orange wire between power seat switch connector terminal "A" and POWER SEATS circuit breaker terminal in fuse block. Recheck system operation.
  6. Check for poor connections at power seat switch terminals. If connections are not okay, go to next step. If connections are okay, go to step 8)  .
  7. Repair poor connection at power seat switch. Recheck system operation.
  8. Replace power seat switch. See POWER SEAT SWITCHES  under REMOVAL & INSTALLATION. Recheck system operation.
  9. Repair open in Black wire between power seat switch connector terminal "D" and ground connection in left door sill, forward of left front seat. Recheck system operation.
Fig 1: Identifying Power Seat Switch Connector Terminals
G99J02292Courtesy of GENERAL MOTORS CORP.