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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 (Brown wire) and ground. If continuity exists, go to next step. If no continuity exists, repair wiring harness open circuit between cruise control switch terminal No. 17 (Brown wire) and ground. Also check for faulty ground.
  2. Check cruise control switch for proper operation. See CRUISE CONTROL SWITCH TEST in this article. Replace faulty cruise control switch and recheck cruise control system. If cruise control switch is okay, reconnect switch and go to next step.
  3. Cruise Control: Disconnect electronic control unit. Check continuity between wiring harness side of ECU terminal No. 19 (White/Red wire) and ground with SET/COAST switch on. See Figure. If continuity exists, go to next step. If no continuity exists, repair wiring harness open circuit between ECU terminal No. 19 (White/Red wire) and terminal No. 5 (White/Red wire) of cruise control switch.
  4. Check continuity between wiring harness side of ECU terminal No. 19 (White/Red wire) and ground with SET/COAST switch off (released). If no continuity exists, replace faulty ECU and recheck cruise control system. If continuity exists, repair wiring harness short circuit between ECU terminal No. 19 (White/Red wire) and terminal No. 5 (White/Red wire) of cruise control switch.
Fig 1: Input Signal Diagnostic Mode Test Procedures Chart (ES250)
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