Cruise Control Malfunction
Cruise Control Malfunction
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Initial Inspection and Diagnostic Overview
* Review Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions provides an overview of each diagnostic category.
Diagnostic Fault Information
Circuit/System Description
The cruise control switch is an input to the body control module (BCM). The BCM monitors the cruise control switch signal circuit in order to detect when the driver has requested to perform a cruise control function. The BCM detects a specific voltage signal on the cruise control switch signal circuit when a switch is applied.
Circuit/System Verification
Important:
* Repair any brake system related symptoms and DTCs before performing this diagnostic.
* Electromagnetic interference (EMI) on the speed sensor signal circuit may cause erratic cruise control operation.
Ignition ON, rotate the steering wheel to both steering stops and observe the scan tool Cruise Control Switch parameter in the BCM while pressing the various cruise control switches. The reading should match accordingly with each depressed switch.
Circuit/System Testing
Important: Repair any brake system related symptoms and DTCs before performing this diagnostic.
1. Ignition OFF, remove the inflatable restraint steering wheel module.
2. Disconnect the harness connector at the steering wheel controls switch - left.
3. Ignition ON, measure for 4.8-5.2 volts at the 5-volt reference circuit terminal 1 and ground.
• If less than the specified range, test the 5-volt reference circuit for an open/high resistance or a short to ground. If the circuit tests normal, replace the BCM.
• If greater than the specified range, test the 5-volt reference circuit for a short to voltage. If the circuit tests normal, replace the BCM.
4. Verify the scan tool Cruise Control Switch parameter is OFF.
• If not the specified value, test the signal circuit terminal 3 for a short to voltage. If the circuit tests normal, replace the BCM.
5. Ignition OFF, connect the harness connector at the steering wheel controls switch - left.
6. Ignition ON, cruise control switch ON, observe the scan tool Cruise Control Switch parameter. The parameter should display ON.
• If not the specified value, test the signal circuit terminal 3 for a short to ground or an open/high resistance. If the circuit tests normal, test or replace the steering wheel controls switch - left.
7. Observe the scan tool Cruise Control Switch parameter while pressing the RES + portion of the cruise control switch. The parameter should display Resume.
• If not the specified value, test or replace the steering wheel controls switch - left.
8. Observe the scan tool Cruise Control Switch parameter while pressing the SET - portion of the cruise control switch. The parameter should display Set.
• If not the specified value, test or replace the steering wheel controls switch - left.
9. Observe the scan tool Cruise Control Switch parameter while pressing the Cancel portion of the cruise control switch. The parameter should display Cancel.
• If not the specified value, test or replace the steering wheel controls switch - left.
10. If the circuits test normal, replace the ECM.
Component Testing
Important: The cruise control switch must be ON in order to properly measure the resistance of the - SET and the + RES switches.
Steering Wheel Controls Switch - Left
1. Ignition OFF, remove the inflatable restraint steering wheel module.
2. Ignition OFF, disconnect the harness connector at the steering wheel controls switch - left.
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 for the On, Off, SET -, RES + and Cancel switches.
• If any of the resistance measurements for the On, Off, SET -, RES + and Cancel switches are not within the listed resistance values, replace the steering wheel controls switch - left.
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure. Verification Tests
* Steering Wheel Control Switch Assembly Replacement