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Test 6, Stoplight Switch

  1. Check stoplight operation. If stoplight system operates properly, go to step 8). If stoplight system does not operate properly, remove and inspect STOP fuse. If STOP fuse is okay, go to step 4). If fuse is blown, replace fuse. Recheck system operation. If fuse fails again, go to next step. If fuse does not fail again, and system is operating properly, test is complete.
  2. Disconnect CC ECU connector. See Figure. Replace STOP fuse. Recheck system operation. Remove and inspect STOP fuse. If fuse is okay, go to next step. If fuse fails again, locate and repair short in wiring harness between stoplight switch and STOP fuse or between CC ECU and STOP fuse.
  3. Depress brake pedal. Remove and inspect STOP fuse. If fuse is okay, replace CC ECU and recheck system operation. If fuse is blown, locate and repair short in wiring harness between stoplight switch and stoplights or between CC ECU and stoplights.
  4. Ensure stoplight switch is installed properly. See STOPLIGHT SWITCH ADJUSTMENT  under ADJUSTMENTS. Adjust switch as necessary and recheck system operation. If switch is adjusted properly, disconnect 4-pin stoplight switch connector and go to next step.
  5. Measure voltage between ground and stoplight switch connector terminal No. 2 (Green/Orange wire). If battery voltage is present, go to next step. If battery voltage is not present, locate and repair open in wiring harness between STOP fuse and stoplight switch connector.
  6. Connect a jumper wire between stoplight switch connector terminal No. 1 (Green/White wire) and terminal No. 2 (Green/Orange wire). Check stoplight operation. If lights are on, go to next step. If lights are off, locate and repair open in wiring harness between stoplight switch connector and stoplights.
  7. Check stoplight switch. See STOPLIGHT SWITCH TEST  under COMPONENT TESTING. Replace switch as necessary and recheck system operation. If switch is okay, reconnect stoplight switch connector and go to next step.
  8. Disconnect CC ECU connector. See Figure. Measure voltage between ground and CC ECU connector terminal No. 1. See Figure. If battery voltage is present, go to next step. If battery voltage is not present, locate and repair open in wiring harness between CC ECU connector and STOP fuse.
  9. With brake pedal depressed, measure voltage between ground and CC ECU connector terminal No. 16. See Figure. If battery voltage is present, replace CC ECU and recheck system operation. If battery voltage is not present, locate and repair open in wiring harness between stoplight switch connector and CC ECU connector.
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