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Test C

  1. Turn ignition and cruise control on. Disconnect cruise control ECU 15-pin connector. Measure voltage between ECU harness connector terminal No. 3 (Red/White wire) and ground. Press SET/ACCEL switch on and off. Battery voltage should exist when switch is on, no voltage should exists when switch is off. If voltage is as specified, go to next step. If voltage is not as specified, repair Red/White, Gray/Yellow or White/Yellow wires, or replace clockspring or SET/ACCEL switch.
  2. Turn ignition on. Disconnect cruise control ECU 15-pin connector. Measure voltage between ECU harness connector terminal No. 5 (Green/Purple wire) and ground. Depress brake pedal. Battery voltage should be present. Release brake pedal, battery voltage should not be present. If voltage is as specified, go to next step. If voltage is not as specified, inspect F B1 fuse (10-amp) in instrument panel fuse block, repair Green/Purple wire, or replace stoplight switch.
  3. Turn ignition off. Disconnect cruise control ECU 15-pin connector. Using ohmmeter, measure resistance between ECU harness connector terminal No. 8 (Black wire) and ground. If resistance is 0-1 ohm, go to next step. If resistance is greater than 0-1 ohm, repair Black wire.
  4. Turn ignition on. Disconnect cruise control ECU 15-pin connector. Measure voltage between ECU harness connector terminal No. 4 (Blue/White wire) and ground. Press RES/DECEL switch on and off. Battery voltage should exist when switch is on, no voltage should exist when switch is off. If voltage is as specified, go to next step. If voltage is not as specified, repair Blue/White wire or replace RES/DECEL switch
  5. Turn ignition on. Disconnect cruise control ECU 15-pin connector. Measure voltage between ECU harness connector terminal No. 11 (Yellow/Pink wire) and ground. With right rear wheel on ground, rotate left rear wheel. Voltage should fluctuate between 0-12 volts as wheel is being turned. If voltage is as specified, go to next step. If voltage is not as specified, repair Yellow/Pink wire.
  6. Turn ignition and cruise control on. Disconnect cruise control ECU 15-pin connector. Install a fused jumper wire between ECU harness connector terminals No. 1 (White/Blue wire) and No. 10 (White/Yellow wire). Install a second fused jumper wire between terminal No. 7 (Black/Red wire) and ground. Cruise control vacuum pump should operate. If pump operates, repair Black/Yellow wire, and go to next step. If vacuum pump does not operate, go to TEST D.
  7. Ensure ignition and cruise control is on. Disconnect cruise control ECU 15-pin connector. Install a fused jumper wire between ECU harness connector terminals No. 1 (White/Blue wire) and No. 10 (White/Yellow wire). Install a second fused jumper wire between ground and ECU harness connector terminals No. 6 (Black/Yellow wire) and No. 7 (Black/Red wire). If cruise control actuator retracts, replace ECU. If actuator does not retract, go to TEST D.
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