Communication Circuit Troubleshooting

Cruise Control Communication Circuit Troubleshooting (A/T)

1. Start the engine.
2. Turn on the cruise control main switch, then drive the vehicle at speeds over 25 mph (40 km/h) with the cruise control.

Does the cruise control operate?

YES - Go to step 3.

NO - Check the cruise control unit or cruise control actuator.

3. Turn the ignition switch OFF.
4. Disconnect the negative cable from the battery.
5. Disconnect powertrain control module (PCM) connector D (17P) and cruise control unit 14P connector.
6. Check for continuity between PCM connector terminal D12 and body ground.

Is there continuity?

YES - Repair short to ground in the wire between PCM connector terminal D12 and the cruise control unit 14P connector terminal No. 8.

NO - Go to step 7.

7. Reconnect PCM connector D (17P) and the cruise control unit 14P connector.




8. Connect the negative cable to the battery.




9. Connect a voltmeter between cruise control unit 14P connector terminal No.8 and body ground.

Test-drive the vehicle at speeds over 25 mph (40 km/h) with the cruise control set, and watch the voltmeter.

Is there about 1 V?

YES - Go to step 9.

NO - Substitute a known-good cruise control unit. If the system works properly, replace the cruise control unit.




10. Connect a voltmeter between PCM connector terminal D12 and body ground. Drive the vehicle at speeds over 25 mph (40 km/h) with the cruise control set, and watch the voltmeter.

Is there about 1 V?

YES - Check for loose connectors of the BLU/ORN wire between the cruise control unit and PCM. If necessary replace the PCM and recheck.

NO - Repair open in the wire between PCM connector terminal D12 and the control unit 14P connector terminal No. 8.