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Ignition Switch Circuit Test

NOTE: If power seat ECU senses ignition is not turned on, it prevents seats from being operated.
  1. At driver's seat, remove bolts for front vertical adjuster. Lift front end of seat cushion slightly for access to power seat ECU. Remove power seat ECU, but leave wiring harness connectors attached. Measure voltage between chassis ground and terminal No. 12 at power seat ECU connector "A". See Figure.
  2. With ignition on, battery voltage should be present. With ignition off, no voltage should be present. If voltage is as specified, return to TROUBLE SHOOTING . If voltage is not as specified, check ECU-IG fuse. If ECU-IG fuse is blown, check for short to ground in Black/Yellow wire. If ECU-IG fuse is okay, repair open circuit between power seat ECU and battery.
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