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Cruise Control Malfunction



Cruise Control Malfunction

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview)provides an overview of each diagnostic category.



Circuit/System Description

The turn signal/multifunction switch is an input to the body control module (BCM). The BCM monitors the cruise control on/off, set/coast and resume/accelerate switches via 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. The BCM sends a serial data message to the ECM indicating the status of the cruise control switches.


Reference Information
Schematic Reference

Cruise Control Schematics (Conventional) (Cruise Control Schematics (Conventional))Cruise Control Schematics (Adaptive) (Cruise Control Schematics (Adaptive))
Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

Cruise Control Description and Operation (Adaptive Cruise) (Cruise Control Description and Operation (Adaptive Cruise))Cruise Control Description and Operation (Conventional Cruise) (Cruise Control Description and Operation (Conventional Cruise))
Electrical Information Reference

* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)

Scan Tool Reference

Control Module References (Programming and Relearning)for scan tool information


Circuit/System Verification

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


Circuit/System Testing

1. Disconnect the harness connector X1 at the turn signal / multifunction switch.
2. Ignition ON, test for greater than 10 volts between the supply voltage circuit terminal 1 and ground.

If less than the specified range, test the supply voltage circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.

3. Verify the scan tool Cruise Control Switch parameter is OFF.

If not the specified value, test the signal circuit terminal 5 for a short to voltage. If the circuit tests normal, replace the BCM.

4. Ignition OFF, connect the harness connector at the turn signal/multifunction switch.
5. Ignition ON, with the cruise control switch in the ON position, observe the scan tool Cruise Control Switch parameter. The parameter should display ON.

If not the specified value, test the signal circuit terminal 5 for a short to ground or an open/high resistance. If the circuit tests normal, test or replace the turn signal / multifunction switch.

6. 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 turn signal / multifunction switch.

7. 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 turn signal / multifunction switch.

8. Observe the scan tool Cruise Cancel switch parameter. The parameter should display Inactive.

If not the specified value, test or replace the steering wheel controls switch - left.

9. If the circuits test normal, test or replace the ECM.



Component Testing

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




Turn Signal/Multifunction Switch
1. Ignition OFF, disconnect the harness connector X1 at the turn signal / multifunction switch.
2. Measure the resistance between the supply voltage circuit terminal 1 and the signal circuit terminal 5. Individually activate and hold each cruise control function switch and compare the resistance reading to the values for the On, Off, SET - and RES + switches.

If any of the resistance measurements for the On, Off, SET - and RES + switches are not within the listed resistance values, replace the turn signal / multifunction switch.








Steering Wheel Controls Switch - Left
1. Ignition OFF, remove the inflatable restraint steering wheel module. Refer to Inflatable Restraint Steering Wheel Module Replacement (Service and Repair) .
2. Ignition OFF, disconnect the harness connector at the steering wheel controls switch - left.
3. Measure the resistance between the supply voltage circuit terminal 1 and the signal circuit terminal 2. Individually activate and hold each gap function switch and compare the resistance reading to the values for the Gap Up, Gap Down, Cancel or the neutral position.

If any of the resistance measurements for the Gap Up, Gap Down, Cancel or neutral position switches are not within the listed resistance values, replace the steering wheel controls - left.








Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

* Steering Wheel Control Switch Assembly Replacement (Service and Repair)
* Turn Signal Multifunction Switch Replacement (Turn Signal Multifunction Switch Replacement)
* Control Module References (Programming and Relearning)for BCM replacement, setup, and programming