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System Inoperative

NOTE: Servo assembly is grounded through mounting bolts. When instructed to connect tester to pin No. 10, connect tester to chassis ground. Ensure mounting bolts are clean and tight.

  1. Check Power To Servo

    Turn ignition on. Check for battery voltage between servo connector pin No. 4 and chassis ground. If battery voltage exists, go to next step. If battery voltage does not exist, check fuses and replace as necessary. If fuses are okay, repair open power circuit. If fuse repeatedly blows check circuit for short to ground and repair as necessary.

  2. Check Stoplight Switch Circuit

    Disconnect servo harness connector. Turn ignition on. With brake released, measure voltage between pin No. 2 at servo connector and ground. If battery voltage exists, go to step 5). If battery voltage does not exist, go to next step.

  3. Check Power To Stoplight Switch

    Disconnect stoplight switch harness connector (located on top of brake pedal). Check for battery voltage at Yellow/Red wires at stoplight switch harness connector. If battery voltage exists, go to next step. If battery voltage does not exist, check for blown fuse or open circuit. Repair as necessary.

  4. Check Stoplight Switch-To-Servo Circuit

    Measure resistance between servo connector pin No. 2 (White wire) and White wire at stoplight switch harness connector. If resistance is less than 5 ohms, replace stoplight switch. If resistance is greater than 5 ohms, repair open circuit between deactivator switch and servo connectors.

  5. Check Stoplight Switch

    With brake pedal released, measure voltage on pin No. 7 (White/Green wire) at servo connector. If battery voltage does not exist, go to next step. If battery voltage exists, ensure brake pedal height and switch are properly adjusted. If adjustment is okay, replace stoplight switch.

  6. Check Stoplight Circuit

    Measure voltage on pin No. 7 at servo connector while depressing brake pedal. If battery voltage exists, go to step 8). If battery voltage does not exist, go to next step.

  7. Check White/Green Wire

    Disconnect stoplight switch connector. Measure resistance of White/Green wire between stoplight switch harness connector and servo connector pin No. 7. If resistance is less than 5 ohms, replace stoplight switch. If resistance is greater than 5 ohms, repair White/Green wire.

  8. Check For Stuck ON Switch

    With no cruise control switches pressed, check voltage on pin No. 6 (Yellow/Blue wire) at servo connector. If battery voltage exists, replace cruise control switch assembly. If battery voltage does not exist, go to next step.

  9. Check ON Switch Operation

    While pressing cruise control ON switch, measure voltage of pin No. 6 (Yellow/Blue wire) at servo connector. If battery voltage exists, go to step 14). If battery voltage does not exist, go to next step.

  10. Check For Power To Clockspring

    Disable air bag system. See AIR BAG RESTRAINT SYSTEM article. Disconnect clockspring connector near top of steering column. Turn ignition on. Check for battery voltage Blue/Black wire at clockspring connector near top of steering column. If battery voltage exists, go to next step. If battery voltage does not exist, replace blown fuse or repair open circuit between fuse panel and clockspring connector.

  11. Check Clockspring

    Disable air bag system. See AIR BAG RESTRAINT SYSTEM article. Disconnect clockspring connector near top of steering column. Remove drivers-side air bag module. Disconnect cruise control command switches. Measure resistance of clockspring circuits between Black/White wire and Green/Orange. Measure resistance between Blue wire and Yellow/Blue wire. If resistance is greater than 0.5 ohm on any circuit, replace clockspring. If resistance is less than 0.5 ohm on all circuits, go to next step.

  12. Check Circuits From Clockspring To Servo

    Disconnect servo electrical connector. Measure resistance between servo terminal No. 6 and Yellow/Blue wire at clockspring connector. See Figure. Measure resistance between servo terminal No. 5 and Green/Orange wire at clockspring connector. If resistance is 5 ohms greater, repair suspect wire(s). If resistance is less than 5 ohms, check circuits for short to ground and repair as necessary. If wires are okay, go to next step.

  13. Check For Stuck Switch

    Disconnect servo connector. Measure resistance between terminals No. 5 and 6 at servo connector. Do not press any cruise control switches on steering wheel. If resistance is greater than 10 k/ohms, go to next step. If resistance is less than 10 k/ohms, replace cruise control command switch assembly.

  14. Check Switch Resistance

    To check switches, measure resistance between pins No. 5 and 6 of servo connector while pressing each command button. If any resistance is not as specified, replace control switch assembly. See COMMAND SWITCH RESISTANCES TABLE. If all resistances are as specified, go to next step.
    COMMAND SWITCH RESISTANCES

    Button Depressed Ohms
    COAST 115-125
    OFF 0-4
    RESUME 2090-2310
    SET/ACCEL 645-715

  15. Check Vehicle Speed Sensor (VSS) Circuit

    Measure resistance of Blue/White and Orange/Black wires (Brown/Light Green wire on models with ABS) between servo pin harness connector and VSS harness connector. Also check circuits for continuity to ground. If resistance is less than 5 ohms, go to next step. If resistance is greater than 5 ohms, repair open in VSS circuit.

  16. Check VSS

    Disconnect VSS. Measure resistance between VSS terminals. If resistance is 200-300 ohms, go to next step. If resistance is not 200-300 ohms, replace VSS.

  17. Check For Broken Or Binding Servo Cable

    Remove servo cable from servo. Check for broken or binding cable by pulling on cable ball slug. Replace cable as necessary. If cable is okay, replace servo.
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