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Speed Control Inoperative

  1. Perform complete visual inspection of system. Repair as necessary. If all connections and components appear to be okay, go to next step.
  2. Unplug harness connector from servo, near master cylinder. Use only DVOM to make measurements specified in steps 3) through 11).
  3. Turn ignition on. Check for battery voltage between servo harness connector pins No. 7 (Purple/Orange wire) and No. 10 (Red/Light Blue wire) at servo. If battery voltage exists, go to next step. If there is no voltage, go to NO POWER TO SERVO test.
  4. With brake pedal in released position, measure voltage between servo harness connector pins No. 4 (Red/Light Green wire) and No. 10 (Red/Light Blue wire). If voltage is zero, stoplight switch is not stuck on. Go to next step. If battery voltage exists, replace stoplight switch.
  5. Turn ignition off. Measure resistance between servo harness connector pins No. 4 (Red/Light Green wire) and No. 10 (Red/Light Blue wire). If resistance is less than 20 ohms, go to next step. If resistance is greater than 20 ohms, repair stoplight circuit.
  6. With ignition off and brake pedal released, measure voltage between servo harness connector pins No. 9 (White/Pink wire) and No. 10 (Red/Light Blue wire). If meter indicates battery voltage, go to next step. If meter indicates zero, refer to, in this article, NO POWER ON DEACTIVATOR SWITCH CIRCUIT  .
  7. With no steering wheel switches pressed, measure voltage between servo harness connector pins No. 5 (Light Blue/Black wire) and No. 10 (Red/Light Blue wire). If voltage is zero, ON switch is not stuck. Go to next step. If battery voltage exists, replace ON switch.
  8. With ignition off, measure voltage between servo harness connector pins No. 5 (Light Blue/Black wire) and No. 10 (Red/Light Blue wire) while pressing ON switch. If battery voltage exists, ON switch is okay. Go to next step. If voltage is zero, refer to, in this article, ON SWITCH INOPERATIVE  test.
  9. With no steering wheel switches pressed, measure resistance between servo harness connector pins No. 5 (Light Blue/Black wire) and No. 6 (Dark Green/Orange wire). If resistance is greater than 3000 ohms, no switches are stuck. Go to next step. If resistance is less than 3000 ohms, replace stuck command switch.
  10. With SET-ACCEL switch pressed, measure resistance between servo harness connector pins No. 5 (Light Blue/Black wire) and No. 6 (Dark Green/Orange wire). If resistance is 640-720 ohms, SET-ACCEL switch is okay. Go to next step. If resistance is not 640-720 ohms, replace SET-ACCEL switch.
  11. Raise and support vehicle with rear wheels clear of ground. Run rear wheels at 30 MPH. Measure voltage between servo harness connector pins No. 3 (Gray/Black wire) and No. 10 (Red/Light Blue wire). If meter indicates 4-5 volts, speed signal is okay. Go to next step. If voltage is zero, service programmable speedometer/odometer module. See INSTRUMENT PANEL - STANDARD article in the ACCESSORIES/SAFETY EQUIPMENT section.
  12. Remove cable from servo. Check for broken cable by pulling end of cable and observing throttle movement. Replace cable if necessary. If cable is okay, replace servo.
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