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Test No. 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 C17. 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 Green/Orange wire between stoplight switch and STOP fuse or in Green/White wire between CC ECU and stoplight switch.
  3. Depress brake pedal. Remove and inspect STOP fuse. If fuse is okay, check CC ECU. See PIN VOLTAGE TESTS . If found to be defective, replace CC ECU and recheck system operation. If fuse is blown, locate and repair short in Green/White wire 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 S13 and go to next step.
  5. Measure voltage between ground and stoplight switch connector S13 terminal No. 2 (Green/Orange wire). If battery voltage exists, go to next step. If battery voltage does not exist, locate and repair open in Green/Orange wire between STOP fuse and stoplight switch connector S13.
  6. Connect a jumper wire between stoplight switch connector S13 terminal No. 1 (Green/White wire) and 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 Green/White wire between stoplight switch connector S13 and stoplights.
  7. Check stoplight switch. See STOPLIGHT SWITCH TEST  under COMPONENT TESTS. Replace switch as necessary and recheck system operation. If switch is okay, reconnect stoplight switch connector S13 and go to next step.
  8. Disconnect CC ECU connector C17. See Figure. With brake pedal depressed, measure voltage between ground and CC ECU connector C17 terminal No. 16 (Green/White wire). See Figure. If battery voltage exists, check CC ECU. See PIN VOLTAGE TESTS . If found to be defective, replace CC ECU and recheck system operation. If battery voltage does not exist, locate and repair open in Green/White wire between CC ECU connector C17 and stoplight switch.
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