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Cruise Control Does Not Work

  1. Disconnect cruise control unit wiring harness connector. Connect voltmeter leads to terminals No. 26 and 17. Turn control switch to ON position. If 12 volts are present, go to next step. If no voltage is present, repair open circuit between terminal No. 26 and fuse panel or terminal No. 17 and ground.
  2. Connect voltmeter leads to terminals No. 16 and 17. If at least 7 volts are present, go to next step. If no voltage is present, repair open circuit between control unit terminal No. 16 and fuse panel or vehicle speed output terminal of instrument panel connector.
  3. On vehicles with manual transmission, go to next step. On vehicles with automatic transmission, move gear shift lever to Drive. Connect voltmeter leads to terminals No. 25 and 17. If 12 volts are present, go to next step. If no voltage is present, repair open circuit between control unit terminal No. 25 and transmission range switch.
  4. Connect voltmeter leads to terminals No. 24 and 17. If 12 volts are present, go to step 6). If no voltage is present, check for voltage between cruise control switch terminal No. 4 and ground. If 12 volts are present, repair open circuit between cruise control switch and cruise control unit connector terminal No. 24. If 12 volts are not present, go to next step.
  5. Check for battery voltage between cruise control switch terminal No. 1 and ground. If 12 volts are not present, repair open circuit between cruise control switch terminal No. 1 and fuse panel. If 12 volts are present, replace cruise control switch.
  6. Remove connector from cruise control actuator. Connect voltmeter to terminals No. 5 and 8. If about 5 volts are present, go to step 8). If no voltage is present, go to next step.
  7. Check for voltage between cruise control actuator terminal No. 5 and ground. If 5 volts are present, repair open circuit between cruise control actuator terminal No. 8 and ground. If no voltage is present, check continuity of circuits between cruise control actuator terminal No. 5 and terminal No. 11 of cruise control unit. Repair wire as necessary. If wire is okay, replace cruise control unit.
  8. Connect voltmeter leads to terminals No. 5 and 6. If about 5 volts are present, go to step 9). If no voltage is present, check for 5 volts between cruise control unit terminals No. 11 and 2. If no voltage is present, replace cruise control unit. If voltage is present, repair circuit between cruise control actuator terminal No. 6 and cruise control unit terminal No. 24.
  9. Connect voltmeter leads to cruise control actuator terminal No. 1 and ground. If 12 volts are present, go to next step. If no voltage is present, check for 12 volts between cruise control unit terminal No. 14 and ground. If no voltage is present, replace cruise control unit. If voltage is present, repair circuit between cruise control actuator terminal No. 1 and cruise control unit terminal No. 14.
  10. Connect voltmeter leads to cruise control actuator terminals No. 1 and 4. If 12 volts are present, go to next step. If no voltage is present, check for 12 volts between cruise control actuator terminals No. 13 and 25. If no voltage is present, replace cruise control unit. If voltage is present, repair circuit between the cruise control actuator terminal No. 4 and the cruise control unit terminal No. 1.
  11. Check for voltage between cruise control actuator terminal No. 2 and ground. If no voltage is present, go to next step. If 12 volts are present, repair related circuits between cruise control actuator, clutch switch (if equipped), light control module and cruise control unit connector terminal No. 18.
  12. Press brake pedal down. Check for voltage between cruise control actuator terminal No. 2 and ground. If 12 volts are present, go to next step. If no voltage is present, repair open circuit between cruise control actuator and brakelight switch.
  13. On vehicles with automatic transmission, disconnect clutch switch connector jumper wire. On vehicles with manual transmission, disconnect clutch switch. Check for voltage between cruise control actuator terminal No. 2 and ground. If 12 volts are present, go to step 15). If no voltage is present, go to next step.
  14. Repair related circuits between cruise control actuator terminal No. 2, cruise control unit terminal No. 18 and clutch switch. If circuits are okay, check cruise control actuator. Refer to CRUISE CONTROL ACTUATOR TEST  under COMPONENT TESTS. If necessary, replace cruise control actuator. If cruise control actuator is okay, replace cruise control unit.
  15. Check circuits between cruise control actuator terminal No. 3 and cruise control unit terminal No. 19. If necessary, repair wiring. If circuits are okay, check cruise control actuator. Refer to CRUISE CONTROL ACTUATOR TEST  under COMPONENT TESTS. If necessary, replace cruise control actuator. If cruise control actuator is okay, replace cruise control unit.
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