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Cruise Control Is Inoperative

  1. Ensure BRAKE (10-amp), STOP (25-amp) and CRUISE (10-amp) fuses are okay. Disconnect cruise control module connector. Turn ignition on. Connect test light between cruise control module connector terminal "F" (Brown wire) and ground. If test light glows, go to next step. If test light does not glow, repair open in Brown wire.
  2. Connect self-powered test light between cruise control module connector terminal "E" (Black/White wire) and ground. If test light glows, go to next step. If test light does not glow, repair open in Black/White wire.
  3. Turn cruise control on. Connect test light between cruise control module connector terminal "A" (Gray wire) and ground. If test light glows, go to step 6). If test light does not glow, go to next step.
  4. Disconnect 48-pin connector C200 (located at base of steering column). Connect test light between C200 connector pin A13 (Brown wire) and ground. If test light glows, go to next step. If test light does not glow, repair open in Brown wire.
  5. Connect self-powered test light between C200 connector pin A13 (Brown wire) and pin A12 (Gray wire). If test light glows, repair open in Gray wire between cruise control module and C200 connector. If test light does not glow, check for open in Brown or Gray pigtail wire in steering column. If circuits are okay, replace multifunction lever. See appropriate STEERING COLUMN SWITCHES article.
  6. Turn cruise control off. Connect test light between cruise control module connector terminal "B" (Dark Blue wire) and ground. If test light does not glow, go to next step. If test light glows, repair short to power in Dark Blue wire.
  7. Turn cruise control on. Connect test light between cruise control module connector terminal "B" (Dark Blue wire) and ground. Press and hold SET/COAST button. If test light glows, go to step 9). If test light does not glow, go to next step.
  8. Ensure 48-pin connector C200 is disconnected. Connect self-powered test light between cruise control module connector terminal "B" (Dark Blue wire) and C200 connector pin A14 (Dark Blue wire). If test light glows, check for open in Dark Blue pigtail wire in steering column. If circuit is okay, replace multifunction lever. See appropriate STEERING COLUMN SWITCHES article. If test light does not glow, repair open in Dark Blue wire between cruise control module and C200 connector.
  9. Connect test light between cruise control module connector terminal "G" (White wire) and ground. If test light glows, go to next step. If test light does not glow, go to step 11).
  10. Disconnect TCC/brakelight switch. Connect self-powered test light between TCC/brakelight switch connector terminals "E" (Orange wire) and "F" (White wire). If test light glows, adjust or replace TCC/brakelight switch. If test light does not glow, repair short to power in White wire.
  11. Connect test light between cruise control module connector terminal "G" (White wire) and ground. Press and hold brake pedal. If test light glows, go to step 13). If test light does not glow, go to next step.
  12. Disconnect TCC/brakelight switch. Connect self-powered test light between TCC/brakelight switch connector terminal "F" (White wire) and cruise control module connector terminal "G" (White wire). If test light glows, adjust or replace TCC/brakelight switch. If test light does not glow, repair open in White wire.
  13. Connect test light between cruise control module connector terminal "D" (Purple wire) and ground. If test light glows, go to step 16). If test light does not glow, go to next step.
  14. Disconnect TCC/brakelight switch. Connect self-powered test light between TCC/brakelight switch connector terminals "D" (Brown wire) and "C" (Purple wire). If test light glows, go to next step. If test light does not glow, adjust or replace TCC/brakelight switch.
  15. Connect test light between TCC/brakelight switch connector terminals "D" (Brown wire) and ground. If test light glows, repair open in Purple wire. If test light does not glow, check for open in Brown wire. Also check for anti-lock brake related trouble codes. See appropriate ANTI-LOCK BRAKES article.
  16. Using voltmeter, check voltage between cruise control module connector terminal "K" (Dark Green/White wire) and ground. If any voltage is read, go to next step. If no voltage is read, go to step 18).
  17. Disconnect VCM 24-pin connector C4 (Natural). Using voltmeter, check voltage between cruise control module connector terminal "K" (Dark Green/White wire) and ground. If battery voltage exists, repair short to power in Dark Green/White wire. If battery voltage does not exist, replace VCM.
  18. Disconnect VCM 24-pin connector C4 (Natural). Connect self-powered test light between cruise control module connector terminal "K" (Dark Green/White wire) and VCM C4 connector terminal No. 3 (Dark Green/White wire). If test light glows, go to next step. If test light does not glow, repair open in Dark Green/White wire.
  19. Connect self-powered test light between cruise control module connector terminal "K" (Dark Green/White wire) and ground. If test light does not glow, go to next step. If test light glows, repair short to ground in Dark Green/White wire.
  20. Reconnect VCM C4 connector. Ensure cruise control module is disconnected. Connect voltmeter between cruise control module connector terminal "K" (Dark Green/White wire) and ground. Turn radio off. While observing voltmeter, drive vehicle at speed. If voltage fluctuates between 0 and 5 volts depending on speed, go to next step. If voltage does not fluctuate between 0 and 5 volts depending on speed, replace VCM.
  21. Continue driving vehicle. Turn radio on. If voltmeter indicated zero volts, replace radio. If voltage fluctuates between 0 and 5 volts depending on speed, replace cruise control module.
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