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Test B

  1. Turn ignition on. Disconnect cruise control ECU 15-pin connector. Connect voltmeter positive lead to terminal No. 10 (White/Yellow wire) and connect negative lead to ground. Turn cruise control switch on. Battery voltage should be present. With cruise control switch off, battery voltage should not exist. If voltage is as specified, go to next step. If voltage is not as specified, inspect E2 fuse (10-amp), repair White/Yellow wire or Green/Light Green wire, or replace cruise control switch.
  2. Turn ignition and cruise control on. Place gear selector in Drive. Disconnect cruise control ECU 15-pin connector. Measure voltage between ECU harness connector terminal No. 9 (Purple/Green wire) and ground. With brake switch vent valve released, battery voltage should exist. With brake switch vent valve depressed, no voltage should exist. If voltage is as specified, go to TEST C. If voltage is not as specified, go to next step.
  3. With ignition on and gear selector in Drive, disconnect brake switch vent valve. Using voltmeter, measure voltage between brake switch harness connector terminal No. 1 (Purple/Yellow wire) and ground. Turn cruise control switch on and off. Battery voltage should exist when switch on, and no voltage when switch is off. If voltage is as specified, repair Purple/Yellow wire or replace brake switch vent valve. If voltage is not as specified, go to next step.
  4. Ensure ignition is on. Disconnect cruise control lock-out relay. Measure voltage between ground and cruise control lock-out relay harness connector terminals No. 30 (White/Gray wire) and No. 86 (White/Gray wire). Turn cruise control switch on and off. Battery voltage should exist when switch is on, and no voltage when switch is off. If voltage is as specified, go to next step. If voltage is not as specified, repair White/Gray wire or White/Yellow wire, or replace diode.
  5. Turn ignition off. Disconnect cruise control lock-out relay. Using ohmmeter, measure resistance between lock-out relay harness connector terminal No. 85 (Black/Yellow wire) and ground. Moving gear selector between gears, resistance should be as specified. See LOCK-OUT RELAY TO GROUND RESISTANCE table. If resistance is as specified, repair Purple/Yellow wire, or replace starter inhibit/reverse switch. If resistance is not as specified, repair Black/Yellow wire, or replace park/neutral position 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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