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Test A

  1. Turn ignition on. Disconnect cruise control ECU 15-pin connector. Connect voltmeter positive lead to cruise control ECU harness connector terminal No. 1 (White/Yellow wire), and negative lead to ground. Battery voltage should exist when cruise control switch is turned on, no voltage when turned off. If battery voltage exists, go to next step. If battery voltage does not exist, inspect E2 fuse, repair White/Yellow wire from cruise control switch to ECU, or Green/Light Green wire from fuse panel to cruise control switch, or replace cruise control switch.
  2. Turn ignition on. Using voltmeter, check voltage between cruise control ECU harness connector terminal No. 2 (Red/White wire) and ground. Turn cruise control switch on. Battery voltage should exist when switch is turned on, no voltage when turned off. If battery voltage exists, go to next step. If battery voltage does not exist, repair Red/White wire between cruise control ECU and cruise cassette (clockspring), repair Red/Yellow wire between cruise cassette and SET/ACCEL switch, or replace cruise cassette or SET/ACCEL switch.
  3. Ensure ignition is on, cruise control switch is in the number one position, and brake pedal is released. Disconnect cruise control ECU 15-pin connector. Using ohmmeter, check resistance between ECU connector terminal No. 3 (Purple/Green wire) and ground. Moving gear selector between gears, ensure resistance is as specified in CRUISE CONTROL ECU TO GROUND RESISTANCE table. If resistance is within specifications, go to next step. If resistance is not within specifications, go to TEST B.
    CRUISE CONTROL ECU TO GROUND RESISTANCE

    Switch Position Resistance (Ohms)
    Park Greater Than 10K
    Reverse 0-1
    Neutral Greater Than 10K
    Drive 0-1
    1, 2 & 3 0-1
  4. Turn ignition off. Disconnect ECU harness connector. Measure resistance between pin No. 8 (Black wire) and ground. If resistance is 0-1 ohm, go to next step. If resistance is greater than one ohm, repair Black wire between ECU and ground.
  5. Ensure ignition and cruise control system are on. Disconnect cruise control ECU 15-pin connector. Using voltmeter, check voltage between cruise control ECU harness connector terminal No. 6 (Blue/Yellow wire) and ground. With RESUME/DECEL switch pressed, battery voltage should exist. With RESUME/DECEL switch released, no voltage should exist. If voltage is as specified, go to next step. If voltage is not as specified, repair Blue/Yellow wire between ECU, cruise cassette (clockspring), RES/DECEL switch and ground, or replace cruise cassette or RES/DECEL switch.
  6. Turn ignition on. Disconnect cruise control ECU 15-pin connector. Measure voltage between terminal No. 5 (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 battery voltage is as specified, go to next step. If voltage is not as specified, repair Yellow/Pink wire between vehicle speed sensor and ECU.
  7. Ensure ignition and cruise control system are on. Ensure cruise control ECU 15-pin connector is disconnected. Connect a fused jumper between ground and cruise control ECU harness connector terminal No. 4 (Black wire). Cruise control actuator should operate. If actuator operates, go next step. If actuator does not operate, go to TEST C.
  8. Turn ignition on. Ensure cruise control ECU 15-pin connector is disconnected. Connect fused jumper wires between cruise control ECU harness connector terminals No. 4 and 7, to ground. Turn cruise control switch on. Cruise control actuator should retract. If actuator retracts, probable cause is cruise control ECU, go to TEST B, step 2). If actuator does not retract, go to TEST C.
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