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Procedure I, Parking Brake Switch Circuit

  1. Brake Fluid Level Switch: Ensure ignition is off. Disconnect brake fluid level switch. Check continuity between wiring harness side of brake fluid level switch terminal No. 2 (White/Black wire) and ground. If continuity exists, go to next step. If no continuity exists, repair wiring harness open circuit between terminal No. 2 (White/Black wire) and ground. Also check for faulty ground.
  2. Check brake fluid level switch operation. See BRAKE FLUID LEVEL SWITCH TEST under TESTING in this article. Replace switch if faulty. If switch is okay, reconnect switch and go to next step.
  3. Parking Brake Switch: Disconnect parking brake switch. Check continuity between wiring harness side of parking brake switch terminal No. 2 and ground. If continuity exists, go to next step. If no continuity exists, repair wiring harness open circuit between terminal No. 2 and ground. Also check for faulty ground.
  4. Check parking brake switch for proper operation. See PARKING BRAKE SWITCH TEST under TESTING in this article. If switch is faulty, replace switch. If switch is okay, reconnect switch and go to next step.
  5. Cruise Control ECU: Disconnect electronic control unit. Turn ignition on. With parking brake lever pulled up, check for battery voltage between wiring harness side of ECU terminal No. 14 (Red/White wire) and ground. See Figure. If voltage is correct, go to next step. If voltage is incorrect, repair wiring harness open circuit between ECU terminal No. 14 (Red/White wire) and parking brake switch.
  6. With parking brake lever released (down), check for battery voltage between wiring harness side of ECU terminal No. 14 (Red/White wire) and ground. If voltage is correct, replace faulty ECU and recheck cruise control system. If voltage is incorrect, repair wiring harness short circuit between ECU terminal No. 14 (Red/White wire) and terminal No. 1 (Red/White wire) of parking brake switch, between terminal No. 1 (Red/White wire) of brake fluid level switch, or parking brake indicator light.
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