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Test B

  1. Turn ignition on. Disconnect cruise control lock-out relay. Connect voltmeter positive lead to relay harness connector Yellow/White wire terminal, 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 Yellow/White wire between lock-out relay and cruise control diode, or White/Yellow wire between cruise control diode and cruise control switch, or replace diode.
  2. Ensure ignition is on, and cruise control ECU is connected. Connect voltmeter positive lead to lock-out relay harness connector terminal No. 87 (Purple/Green wire), and ground negative lead. Turn cruise control switch on. Battery voltage should be present. If voltage is present, go to next step. If voltage is not present, repair Purple/Green wire between lock-out relay and cruise control ECU, or replace ECU.
  3. Turn ignition off. Using ohmmeter, measure resistance between lock-out relay harness connector terminal No. 30 (Purple/Green wire) and ground. With brake pedal released, resistance should be 0-1 ohms. With brake pedal depressed, resistance should be greater than 10K ohms. If resistance is as specified, go to next step. If resistance is not as specified, repair Purple/Green wire between brake switch vent valve and lock-out relay, or Green/Purple wire between brake switch vent valve and stoplights, or replace brake switch vent valve.
  4. Turn ignition off. Using ohmmeter, measure resistance between lock-out relay harness connector terminal No. 85 (Black/Orange wire) and ground. Moving gear selector between gears, resistance should be as specified in LOCK-OUT RELAY TO GROUND RESISTANCE table. If resistance is as specified, replace cruise control lock-out relay. If resistance is not as specified, repair Black/Orange wire between lock-out relay and inhibit/reverse switch, or replace inhibit/reverse switch.
LOCK-OUT RELAY TO GROUND RESISTANCE

Switch Position Resistance (Ohms)
Park 0-1
Reverse Greater Than 100
Neutral 0-1
Drive Greater Than 100
1, 2 & 3 Greater Than 100
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