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Cruise Control Servo Test

NOTE: Servo connector terminals are marked on harness side of connector.
  1. Disconnect cruise control electrical connector. Using a fused jumper, connect servo terminal "C" to chassis ground. Jumper servo terminal "A" to battery positive. Run engine for 2 minutes, then turn off.
  2. Jumper servo terminal "E" to battery positive. Servo should pull throttle cable in and hold it in. If servo does not pull throttle cable in, check for 10 in. Hg supply vacuum.
  3. Check vacuum hoses for restrictions and servo throttle linkage for binding. Check vacuum hoses, vacuum source and check valve for leaks. Check brake release valve for leaks and adjustment. If all hoses, throttle linkage and valves are okay, replace servo.
  4. If servo pulls throttle cable in, depress brake pedal. Servo should release throttle cable. If throttle cable did not release, check vacuum hose to brake release valve on brake pedal support for kinks and restrictions. Check brake release valve adjustment.
  5. If throttle cable did release, disconnect fused jumper from servo terminal "C". Run engine for 2 minutes, then turn engine off. Reconnect fused jumper between servo terminal "C" and chassis ground.
  6. After servo pulls throttle cable in, disconnect fused jumper wire from servo terminal "A". Servo should release throttle cable. If throttle cable is not released, replace servo. If throttle is released, ensure servo terminal "C" is grounded. Ensure circuits No. 402 (Light Green wire) and No. 403 (Dark Blue/White wire) are not open or grounded. If servo terminal "C" has a good ground and Light Green and Dark Blue/White wires are okay, replace PCM.
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