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 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.
Circuit/System Verification
Ignition ON, Cruise Control Switch ON, verify that the Cruise Set/Coast and Cruise Resume/Accel. Switch parameters read Inactive (OFF). The switch parameter should change to Active (ON) and back to Inactive (OFF) as the switch is pressed and released.
Circuit/System Testing
Important: In order to avoid misdiagnosis, inspect for the following:
* Verify there are no DTCs set as current. If any DTCs are set as current, refer to Diagnostic Trouble Code (DTC) List - Vehicle and perform the appropriate diagnostics/repairs before proceeding with symptom based diagnostics Diagnostic Trouble Code Descriptions
* Inspect the cruise control switches for any sticking or binding conditions.
* Inspect for proper operation of the stop lamps..
1. Ignition OFF, disable the SIR system. Refer to SIR Disabling and Enabling.
2. Disconnect the turn signal multifunction switch harness connector X4.
3. Ignition ON, verify the Cruise Control On/Off Switch parameter displays Off.
^ If the Cruise Control On/Off Switch parameter displays On, test the cruise ON switch signal circuit for a short to voltage. If the circuit tests normal, replace the ECM.
4. Test for B+ between the turn signal multifunction switch harness connector X4 terminal A and ground.
^ If the reading is less than specified, test the cruise control switch voltage supply circuit for an open or high resistance.
5. Connect a 3-amp fused jumper between terminals A and B of the turn signal multifunction switch harness connector X4. Verify the Cruise Control On/Off Switch parameter displays On.
^ If the Cruise On/Off Switch parameter displays Off, test the cruise control ON switch signal circuit for an open/high resistance or short to ground. If the circuit tests normal, replace the ECM.
6. Verify the Cruise Control Resume/Accel. Switch parameter displays Off.
^ If the Cruise Control Resume/Accel. Switch parameter displays On, test the cruise control resume/accel. switch signal circuit for a short to voltage. If the circuit tests normal, replace the ECM.
7. Connect a 3-amp fused jumper between terminals A and C of the turn signal multifunction switch harness connector X4. Verify the Cruise Control Resume/Accel. Switch parameter displays On.
^ If the Cruise Resume/Accel. Switch parameter displays Off, test the cruise control resume/accel. switch signal circuit for an open/high resistance or short to ground. If the circuit tests normal, replace the ECM.
8. Verify the Cruise Control Set/Coast Switch parameter displays Off.
^ If the Cruise Control Set/Coast Switch parameter displays On, test the cruise control set/coast switch signal circuit for a short to voltage. If the circuit tests normal, replace the ECM.
9. Connect a 3-amp fused jumper between terminals A and D of the turn signal multifunction switch harness connector X4. Verify the Cruise Control Set/Coast Switch parameter displays On.
^ If the Cruise Control Set/Coast Switch parameter displays Off, test the cruise control set/coast switch signal circuit for an open/high resistance or short to ground. If the circuit tests normal, replace the ECM.
10. If all circuits test normal, replace the cruise control switch.
Component Testing
1. Ignition OFF, disable the SIR system. Refer to SIR Disabling and Enabling.
2. Disconnect the turn signal multifunction switch harness connector X4.
3. Test for infinite resistance between terminals A and B of the turn signal multifunction switch.
^ If not the specified value, replace the turn signal multifunction switch.
4. Turn the cruise control ON/OFF switch ON. Test for less than 1 ohm between terminals A and B of the turn signal multifunction switch.
^ If not the specified value, replace the turn signal multifunction switch.
5. Test for infinite resistance between terminals A and D of the turn signal multifunction switch.
^ If not the specified value, replace the turn signal multifunction switch.
6. Press and hold the set/coast switch. Test for less than 1 ohm between terminals A and D of the turn signal multifunction switch.
^ If not the specified value, replace the turn signal multifunction switch.
7. Test for infinite resistance between terminals A and C of the turn signal multifunction switch.
^ If not the specified value, replace the turn signal multifunction switch.
8. Press and hold the resume/accel. switch. Test for less than 1 ohm between terminals A and C of the turn signal multifunction switch.
^ If not the specified value, replace the turn signal multifunction switch.
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure. Verification Tests
* Turn Signal Multifunction Switch Replacement