The cruise control switch is an input to the engine control module (ECM)/powertrain control module (PCM). The ECM (3.6L) /PCM (3.8L) monitors the cruise control set/coast and resume/accelerate switch signal circuit in order to detect when the driver has requested to perform a cruise control function. The ECM/PCM detects a specific voltage signal on the cruise control set/coast and resume/accelerate switch signal circuit when a switch is applied. The BCM monitors the cruise control cancel switch in order to detect when the drive has requested to perform a cruise control cancellation. The BCM sends a GMLAN serial data message to the ECM/PCM indicating the status of the cruise cancel switch.

Caution: Refer to SIR Caution in the Preface section.

Disable the inflatable restraint steering wheel module when performing this diagnostic table. Refer to SIR Disabling and Enabling .

Important: Repair any brake system related symptoms and DTCs before performing this diagnostic.

In order to avoid misdiagnosis, inspect for the following:

Schematic Reference

Cruise Control Schematics

Connector End View Reference

Cruise Control Connector End Views

Electrical Information Reference

Scan Tool Reference

Scan Tool Data List

Caution: Refer to SIR Caution in the Preface section.

Disable the inflatable restraint steering wheel module when performing this diagnostic. Refer to SIR Disabling and Enabling .

Important: Repair any brake system related symptoms and DTCs before performing this diagnostic.

1. Ignition OFF, remove the inflatable restraint steering wheel module. Refer to Inflatable Restraint Steering Wheel Module Replacement .
2. Disconnect the harness connector of the cruise control switch.
3. Ignition ON, verify that a test lamp illuminates between the steering wheel control supply voltage circuit terminal 1 and ground.

⇒	If the test lamp does not illuminate, test the cruise control supply voltage circuit for an open/high resistance or a short to ground.

4. Ignition OFF, disconnect the harness connector C3 of the BCM.
5. Ignition ON, verify that a test lamp does not illuminate at the harness connector of the BCM C3 between the cruise cancel switch signal circuit terminal 6 and ground.

⇒	If the test lamp illuminates, test the cruise cancel switch signal circuit for a short to voltage.

6. Ignition OFF, install a fused jumper at the harness connector of the cruise control switch between the steering wheel control supply voltage circuit terminal 1 and the cruise cancel switch signal circuit terminal 5.
7. Ignition ON, verify that a test lamp illuminates at the harness connector of the BCM C3 between the cruise cancel switch signal circuit terminal 6 and ground.

⇒	If the test lamp does not illuminate, test the cruise cancel switch signal circuit for an open/high resistance, or a short to ground.

8. Ignition OFF, connect the harness connector C3 at the BCM. Disconnect the harness connector C1 at the PCM (3.8L)/C2 at the ECM (3.6L).
9. Connect the fused jumper at the harness connector of the cruise control switch between the steering wheel control supply voltage circuit terminal 1 and the cruise control switch signal circuit terminal 3.
10. Ignition ON, connect a test lamp at the harness connector of the PCM/ECM between the cruise control switch signal circuit terminal 44 (3.8L) or terminal 59 (3.6L) and ground.

⇒	If the test lamp illuminates, test the cruise control switch signal circuit for a short to voltage.

⇒	If the test lamp does not illuminate, test the cruise control switch signal circuit for an open/high resistance, or a short to ground.

11. If the circuits test normal, test the component. If the component tests normal, replace the PCM/ECM.

Caution: Refer to SIR Caution in the Preface section.

Disable the inflatable restraint steering wheel module when performing this diagnostic. Refer to SIR Disabling and Enabling .

Important: The cruise control switch must be ON in order to properly measure the resistance of the - SET, the + RES, and the Cancel switches.

1. With the ignition OFF, remove the inflatable restraint steering wheel module. Refer to Inflatable Restraint Steering Wheel Module Replacement .
2. With the ignition OFF, disconnect C277 at the inflatable restraint steering wheel module coil.
3. Measure the resistance between terminals 1 and 3 at the cruise control switch side of the connector. Individually activate and hold each cruise control function switch and compare the resistance reading to the values on the schematic for the ON/OFF, - SET, and the + RES switches.

⇒	If any of the resistance measurements for the OFF, ON, - SET, and + RES switches are not within the listed resistance values, replace the cruise control switch assembly.

4. Measure the resistance between terminals 1 and 5 at the cruise control switch side of the connector. Activate and hold the cruise cancel switch and compare the resistance reading to the value of the Cancel switch listed below.

⇒	If the Cancel switch is not within the listed resistance value, replace the cruise control switch assembly.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.