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Test No. 5

NOTE: Rear wiper motor is controlled by instrument panel Electronic Control Unit (ECU). If instrument panel ECU failure exists, rear wiper motor will still operate in high-speed.

  1. Check WIPER Fuse

    Remove WIPER fuse from driver's side fuse/relay box located near driver's side kick panel. See Figure.
  2. Using ohmmeter, ensure continuity exists across fuse. If fuse is okay, go to next step. If fuse is blown, check for short circuit in wiring circuit to the fuse and instrument panel ECU. See WIRING DIAGRAMS . Instrument panel ECU is located behind center of instrument panel and contains a 14-pin, 18-pin and 22-pin electrical connector. See Figure. Replace fuse and repair wiring as necessary.
  3. Check Voltage At Terminal No. 3 & 12 On Connector "C" (14-Pin Connector) At Instrument Panel ECU Remove necessary components for access to instrument panel ECU. Instrument panel ECU is located behind center of instrument panel and contains a 14-pin, 18-pin and 22-pin electrical connector. See Figure.
  4. Ensure ignition is off. Disconnect electrical connectors at instrument panel ECU. Turn ignition on. Using voltmeter, check voltage between terminals No. 3 and 4 on connector "C" (14-pin connector) at instrument panel ECU. Using voltmeter, check voltage between terminals No. 4 and 12 on connector "C" (14-pin connector) at instrument panel ECU.
  5. Voltage should be 10-14 volts. If voltage is not within specification, go to next step. If voltage is within specification, go to the next test listed. See appropriate TROUBLE SHOOTING SYMPTOMS table under TROUBLE SHOOTING .

  6. Check Rear Wiper Relay

    Check operation of rear wiper relay. See WIPER/WASHER SYSTEMS article. If rear wiper relay operates properly, go to next step. If rear wiper relay is defective, replace rear wiper relay.

  7. Check Rear Wiper Motor

    Check operation of rear wiper motor. See WIPER/WASHER SYSTEMS article. If rear wiper motor operates properly, go to next step. If rear wiper motor is defective, replace rear wiper motor.

  8. Check Rear Wiper Motor Wiring

    Check for defective connectors and wiring between rear wiper motor and instrument panel ECU. See WIRING DIAGRAMS .
  9. If connectors and wiring are okay, go to the next test listed. See appropriate TROUBLE SHOOTING SYMPTOMS table under TROUBLE SHOOTING . If connectors or wiring are defective, repair as necessary.
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