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.
Diagnostic Fault Information
Circuit/System Description
The cruise control switch is an input to the engine control module (ECM). The ECM monitors the cruise control switch signal circuits in order to detect when a cruise control function switch has been activated. The ECM detects a voltage signal when a cruise control function switch is applied.
Reference Information
Schematic Reference
Cruise Control Schematics (Electrical Diagrams)
Connector End View Reference
Component Connector End Views (Connector Views)
Description and Operation
Cruise Control Description and Operation (Description and Operation)
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
Ignition ON, cruise control switch ON, observe the Cruise Set/Coast and Cruise Resume/Accel. Switch parameters while pressing and releasing each switch. The switch parameters should change between Active and Inactive as the switch is pressed and released.
Circuit/System Testing
1. Ignition OFF, disconnect the X4 harness connector at the turn signal/multifunction switch.
2. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal A and ground.
• If the test lamp does not illuminate, test the circuit for a short to ground or an open/high resistance.
3. Verify the Cruise Control ON/OFF Switch parameter displays Off.
• If not the specified value, test the signal circuit terminal B for a short to voltage. If the circuit tests normal, replace the ECM.
4. Install a 3A fused jumper wire between the signal circuit terminal B and the B+ circuit terminal A. Verify the Cruise Control ON/OFF Switch parameter displays On.
• If not the specified value, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the ECM.
5. Verify that the scan tool Cruise Set/Coast Switch parameter displays Inactive.
• If not the specified value, test the signal circuit terminal C for a short to voltage. If the circuit tests normal, replace the ECM.
6. Install a 3A fused jumper wire between the signal circuit terminal C and the B+ circuit terminal A. Verify the scan tool Cruise Set/Coast Switch parameter displays Active.
• If not the specified value, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the ECM.
7. Verify that the scan tool Cruise Resume/Accel. Switch parameter displays Inactive.
• If not the specified value, test the signal circuit terminal D for a short to voltage. If the circuit tests normal, replace the ECM.
8. Install a 3A fused jumper wire between the signal circuit terminal D and the B+ circuit terminal A. Verify the scan tool Cruise Resume/Accel. Switch parameter displays Active.
• If not the specified value, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the ECM.
9. If all circuits test normal, test or replace the turn signal/multifunction switch.
Component Testing
1. Disconnect the X4 harness connector at the turn signal/multifunction switch.
2. Test for infinite resistance between terminal A and terminal B at the turn signal/multifunction switch.
• If not the specified value, replace the turn signal/multifunction switch.
3. Turn the cruise control ON/OFF switch ON. Test for less than 1 ohm between terminal A and terminal B at the turn signal/multifunction switch.
• If not the specified value, replace the turn signal/multifunction switch.
4. Test for infinite resistance between terminals A and C at the turn signal/multifunction switch.
• If not the specified value, replace the turn signal/multifunction switch.
5. Press and hold the Set/Coast switch. Test for less than 1 ohm between terminal A and terminal C at the turn signal/multifunction switch.
• If not the specified value, replace the turn signal/multifunction switch.
6. Test for infinite resistance between terminal A and terminal D at the turn signal/multifunction switch.
• If not the specified value, replace the turn signal/multifunction switch.
7. Press and hold the Resume/Accel. switch. Test for less than 1 ohm between terminal A and terminal D at the turn signal/multifunction switch.
• If not the specified value, replace the turn signal/multifunction switch.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* Turn Signal Multifunction Switch Replacement (Turn Signal Multifunction Switch Replacement)
* Control Module References (Programming and Relearning) for ECM replacement, setup, and programming