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Cruise Control Does Not Engage

  1. Ensure BRAKE (10-amp), STOP/HAZ (20-amp) and CRUISE (10-amp) fuses are okay. Turn ignition switch to RUN position. Turn cruise control off. Disconnect cruise control module. Connect test light between 48-pin C266 connector (located under left side of steering column, near firewall) terminal A13 (Brown wire) and ground. If test light glows, go to next step. If test light does not glow, repair open in Brown wire between C266 connector and fuse block.
  2. Connect test light between cruise control module connector terminal "A" (Gray wire) and ground. If test light does not glow, go to next step. If test light glows, check for short to power in Gray wire. If circuit is okay, replace cruise control switch.
  3. Connect test light between cruise control module connector terminal "C" (Gray/Black wire) and ground. If test light does not glow, go to next step. If test light glows, check for short to power in Gray/Black wire. If circuit is okay, replace cruise control switch.
  4. 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, check for short to power in Dark Blue wire. If circuit is okay, replace cruise control switch.
  5. Turn cruise control on. Connect test light between C266 connector terminal A12 (Gray wire) and ground. If test light glows, go to next step. If test light does not glow, replace cruise control switch.
  6. Connect test light between cruise control module connector terminal "A" (Gray wire) and ground. If test light glows, go to next step. If test light does not glow, repair open in Gray wire.
  7. 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.
  8. 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.
  9. Connect test light between C266 connector terminal A12 (Gray wire) and ground. Press and hold RESUME/ACCEL switch. If test light glows, go to next step. If test light does not glow, replace cruise control switch.
  10. Connect test light between cruise control module connector terminal "C" (Gray/Black wire) and ground. Press and hold RESUME/ACCEL switch. If test light glows, go to next step. If test light does not glow, repair open in Gray/Black wire.
  11. Connect test light between cruise control module connector terminal "B" (Dark Blue wire) and ground. Press and hold SET/COAST switch. If test light glows, go to step 13). If test light does not glow, go to next step.
  12. Connect test light between C266 connector terminal A14 (Dark Blue wire) and ground. Press and hold SET/COAST switch. If test light glows, repair open in Dark Blue wire. If test light does not glow, replace cruise control switch.
  13. Ensure brake pedal is not pressed. 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 15).
  14. Leaving test light connected, disconnect brakelight switch. If test light glows, repair short to power in White wire. If test light does not glow, replace brakelight switch.
  15. Leaving test light connected, depress brake pedal. If test light glows, go to next step. If test light does not glow, repair open in White wire.
  16. Connect test light between cruise control module connector terminal "D" (Purple wire on A/T models, Brown/White wire on M/T models) and ground. If test light glows, go to next step. If test light does not glow, go to step 18).
  17. Leaving test light connected, depress brake pedal. If test light does not glow, go to step 20) (M/T) or 23) (A/T). If test light glows, check for short to power in Purple or Brown/White wire. If circuit is okay, replace brakelight switch.
  18. Connect test light between brakelight switch connector terminal "E" (Purple wire) and ground. If test light does not glow, go to next step. If test light glows on M/T models, go to step 21). If test light glows on A/T models, repair open in Purple wire.
  19. Connect test light between brakelight switch connector terminal "F" (Brown wire) and ground. If test light glows, replace brakelight switch. If test light does not glow, repair open in Brown wire.
  20. Release brake pedal. Leaving test light connected, press clutch pedal. If test light glows, replace clutch pedal switch. If test light does not glow, go to step 23).
  21. Connect test light between clutch pedal switch terminal "B" (Purple wire) and ground. If test light glows, go to next step. If test light does not glow, repair open in Purple wire.
  22. Connect test light between clutch pedal switch terminal "D" (Brown/White wire) and ground. If test light glows, repair open in Brown/White wire. If test light does not glow, replace clutch pedal switch.
  23. Turn ignition off. Disconnect VCM. 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.
  24. Connect self-powered test light between cruise control module connector terminal "K" (Dark Green/White wire) and VCM Black 24-pin connector C4, 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.
  25. Reconnect cruise control module. Turn ignition on. Turn cruise control on. Using voltmeter, check voltage between VCM Black 24-pin connector C4, terminal No. 3 (Dark Green/White wire) and ground. If reading is greater than 4.5 volts, check for poor connections at VCM. If connections are okay, replace VCM. If reading is less than 4.5 volts, check for poor connections at cruise control module. If connections are okay, replace cruise control module.
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