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Position Sensor Power Source Circuit Test

NOTE: Use this procedure to check for problems in power supply circuit between driver's seat ECU and each position sensor.
  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). Remove driver's seat ECU, leaving wiring harness connectors attached.
  2. Turn ignition on. While seat is moving (operate seat switch), measure voltage between chassis ground and driver's seat ECU connector "B", terminal No. 6 (Violet wire). See Figure.
  3. If voltage is 7-9 volts during switch operation, return to TROUBLE SHOOTING . If voltage is not 7-9 volts during switch operation, check for open or short in Violet wire between position sensors and ECU. See WIRING DIAGRAMS . If circuits are okay, replace driver's seat ECU.
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