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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 as necessary 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 wiring harness connectors attached.
  2. Measure voltage between chassis ground and terminal No. 6 (Green/White wire) at driver's power seat ECU connector "A". See Figure.
  3. On all models, with brake pedal depressed, battery voltage should be present. With brake pedal released, no voltage should be present. 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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