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Procedure B, Set/Coast Switch Circuit

  1. Cruise Control Switch:  Ensure ignition is off. Disconnect cruise control switch. Check continuity between wiring harness side of cruise control switch terminal No. 17 (20-pin connector) and ground. See Figure. If continuity exists, go to next step. If no continuity exists, repair open circuit in wire harness between cruise control switch terminal No. 17 (20-pin connector) and ground. Also check for faulty ground.
  2. Check cruise control switch for proper operation. See CRUISE CONTROL SWITCH TEST  under TESTING. If cruise control switch is faulty, replace and recheck cruise control system. If cruise control switch is okay, reconnect switch and go to next step.
  3. Cruise Control ECU:  Disconnect ECU. Check continuity between wiring harness side of ECU terminal No. 19 and ground with cruise control switch in SET/COAST position. See Figure. If continuity exists, go to next step. If no continuity exists, repair open circuit in wire harness between ECU terminal No. 19 and cruise control switch terminal No. 5 (20-pin connector).
  4. Release control switch from SET/COAST position, and check continuity between wiring harness side of ECU terminal No. 19 and ground. If no continuity exists, replace faulty ECU, and recheck cruise control system. If continuity exists, repair short circuit in wire harness between ECU terminal No. 19 and cruise control switch terminal No. 5 (20-pin connector).
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