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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 power 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 power seat ECU (do not lift too far; harness clamp may come loose). Remove driver's power seat ECU, but leave electrical connectors attached.
  2. Turn ignition on. While seat is moving (operate seat switch), measure voltage between chassis ground and the following terminal of driver's power seat ECU connector.
  3. If 7-9 volts is present, check next item listed under TROUBLE SHOOTING. If 7-9 volts is not present, check for faulty circuit between each position sensor and same terminal in previous step. If circuits are okay, replace driver's power seat ECU.