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Power Seat Switch Circuit Test

  1. 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).
  2. Remove driver's seat ECU, leaving wiring harness connectors attached. Connect voltmeter negative lead to terminal No. 18 at ECU connector "B" (Blue/Red wire). See Figure.
  3. With driver's power seat switch in specified position, connect voltmeter positive lead to specified terminal of driver's power seat switch. See DRIVER'S SEAT SWITCH CIRCUIT TEST  table. See Fig 1. With switch in neutral position (off), battery voltage should be present. With switch in any active position (up, down, etc.), no voltage should be present.
  4. If voltage is as specified, return to TROUBLE SHOOTING . If voltage is not as specified, check switch. See DRIVER'S POWER SEAT SWITCH TEST  under COMPONENT TESTING. If switch is okay, check suspect circuits between driver's seat ECU and switch. If circuit is okay, replace driver's seat ECU.
DRIVER'S SEAT SWITCH CIRCUIT TEST

Switch Position Terminal No.
(1)
Wire Color
Slide
Forward 1 Blue
Backward 2 Blue/Black
Front
Up 5 Blue/Yellow
Down 6 Blue/White
Rear
Up 9 Yellow/Green
Down 8 Yellow
Recline
Forward 4 Yellow/Red
Backward 3 Yellow/Black
(1) See Fig 1.
Fig 1: Identifying Driver's Seat Switch Connector Terminals
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