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Test C

  1. Turn ignition on. Disconnect cruise control vacuum pump connector. Connect voltmeter positive lead to vacuum pump connector terminal No. 82a (White/Yellow wire), and negative lead to ground. Turn cruise control switch on. Battery voltage should be present. If battery voltage is present, go to next step. If battery voltage is not present, repair White/Yellow wire between vacuum pump and cruise control switch.
  2. Turn ignition off. Ensure cruise control vacuum pump is disconnected. Connect a fused jumper wire between battery positive terminal and vacuum pump connector terminal No. 82a (White/Yellow wire). Connect a second jumper wire between ground and vacuum pump connector terminals No. 81 and 81a (Black wire). Actuator should retract. If actuator retracts, repair Black wire between vacuum pump and cruise control ECU. If actuator does not retract, check for possible vacuum leak or restriction, or replace brake switch vent valve or cruise control vacuum pump.
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