Component Tests and General Diagnostics

Cruise Control Communication Circuit Troubleshooting (CVT)

NOTE: After troubleshooting, perform the engine control module (ECM) idle learn procedure.

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. Wait for 1 minute. If the radiator fan is running, wait for 1 minute after the radiator fan stops.
5. Disconnect transmission control module (TCM) connector A (31P) and cruise control unit 14P connector.




6. Check for continuity between TCM connector terminal A27 and body ground.

Is there continuity?

YES - Repair short to ground in the wire between TCM connector terminal A27 and the cruise control unit 14P connector terminal No.8.

NO - Go to step 7.

7. Reconnect TCM connector A (31P) and the cruise control unit 14P connector.




8. 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.




9. Connect a voltmeter between TCM connector terminal A27 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 TCM. If necessary replace the TCM and recheck.

NO - Repair open in the wire between TCM connector terminal A27 and the control unit 14P connector terminal No.8.