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Stoplight Switch Circuit Test

NOTE: If driver's seat ECU senses 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. See EXTERIOR LIGHTS wiring diagram under WIRING DIAGRAMS . At driver's seat, remove bolts for front vertical adjuster. Lift front end of seat cushion slightly for access to driver's seat ECU (do not lift too far; harness clamp may come loose). Remove driver's seat ECU, but leave wiring harness connectors attached.
  2. Measure voltage between chassis ground and terminal No. 6, at driver's seat ECU connector "A". See Figure. With brake pedal depressed, battery voltage should be present. With brake pedal released, no voltage should be present. If voltage is okay, return to TROUBLE SHOOTING . If voltage is not as specified, repair circuit between driver's seat ECU and stoplight switch (Green/White wire).
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