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Stoplight Switch Circuit Test

NOTE: If driver's power seat ECU senses that the brake pedal is being pressed, it prevents seat from being moved to memorized position.
  1. If stoplights do not operate, repair them before continuing. At driver's seat, remove bolts for front vertical adjuster. Lift front end of seat cushion slightly for access to driver's power seat ECU (do not lift too far; harness clamp may come loose). Remove driver's power seat ECU, but leave electrical connectors attached.
  2. Measure voltage between chassis ground and terminal No. 6 of driver's power seat ECU connector "A". See Figure. With brake pedal pressed, battery voltage should be present. With brake pedal released, no voltage should be present.
  3. If voltage is not as specified, repair circuit between driver's power seat ECU and stoplight switch. If voltage is okay, go to next item listed under TROUBLE SHOOTING.
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