The cruise control switches are an input to the engine control module (ECM). The ECM monitors the cruise control switch signal circuits in order to detect when the driver has requested a cruise control function. The ECM module detects a voltage signal on the appropriate switch signal circuit when a switch is applied.

Verify the stop lamps operate properly. Refer to Exterior Lighting Systems Description and Operation.

Schematic Reference

Cruise Control Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Cruise Control Description and Operation

Electrical Information Reference

Scan Tool Reference

Control Module References for scan tool information

Engine ON, while rotating the steering wheel to both steering stops, observe the scan tool Cruise Control Switch parameter while pressing each of the cruise control switches. The parameter should toggle between ON, OFF, Resume, Set, as the applicable switch is pressed.

1. Ignition OFF, disconnect the harness connector at the auto cruise switch.
2. Ignition OFF, test for less than 10 ohms between the ground circuit terminal 4 and ground.

⇒	If greater than the specified value, test the ground circuit for an open/high resistance.

3. Ignition ON, test for B+ between the B+ circuit terminal 1 and ground.

⇒	If less than the specified value, test the circuit for a short to ground or an open/high resistance.

4. Verify the scan tool ON/OFF Switch parameter displays OFF

⇒	If the parameter displays ON, test the signal circuit terminal 2 for a short to voltage. If the circuit tests normal, replace the ECM.

5. Connect a 3-amp fused jumper between the B+ circuit terminal 1 and the signal circuit terminal 2 at the auto cruise switch harness connector. Verify the scan tool Cruise ON/OFF Switch parameter displays ON.

⇒	If not the specified value, test the signal circuit terminal 2 of the auto cruise switch harness for a short to ground or an open/high resistance. If the circuit tests normal, replace the ECM.

6. Ignition OFF, reconnect the harness connector at the auto cruise switch.
7. Ignition ON, auto cruise switch ON, verify the scan tool ON/OFF Switch parameter displays ON.

⇒	If not the specified value, replace the auto cruise switch.

8. Ignition OFF, disconnect the X1 and X2 harness connectors at the turn signal/multifunction switch.
9. Verify the scan tool Cruise Set/Coast Switch parameter displays OFF.

⇒	If not the specified value, test the signal circuit terminal 15 for a short to voltage. If the circuit tests normal, replace the ECM.

10. Verify the scan tool Cruise Resume/Accel. Switch parameter displays OFF.

⇒	If not the specified value, test the signal circuit 28 for a short to voltage. If the circuit tests normal, replace the ECM.

11. Connect a 3-amp fused jumper between connector X1 terminal 16 and connector X1 terminal 15. Verify the scan tool Cruise Set/Coast Switch parameter displays ON.

⇒	If not the specified value, test the signal circuit terminal 15 for a short to ground or an open/high resistance. If the circuit tests normal, replace the ECM.

12. Connect a 3-amp fused jumper between connector X1 terminal 16 and connector X2 terminal 28. Verify the scan tool Cruise Resume/Accel. switch parameter displays ON.

⇒	If not the specified value, test the signal circuit terminal 28 for a short to ground or an open/high resistance. If the circuit tests normal, replace the ECM.

13. If all circuits test normal, test or replace the turn signal/multifunction switch.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.