Steering Wheel Controls Malfunction
Steering Wheel Controls 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 instrument panel cluster (IPC) supplies a regulated voltage supply to the steering wheel control switches and monitors the return signal. Each switch state is associated with a specific resistance value. When a switch is depressed a specific voltage drop occurs across the resistor unique to that switch. The IPC is able to identify which switch was depressed by recognizing the voltage drop associated with that switch and responds to the selected request.
Reference Information
Schematic Reference
Steering Wheel Secondary/Configurable Control Schematics (Steering Wheel Secondary/Configurable Control Schematics)
Connector End View Reference
Component Connector End Views (Connector Views)
Description and Operation
Steering Wheel Controls Description and Operation (Steering Wheel Controls 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, while depressing the individual push button steering wheel control switches, observe the scan tool and verify the status of the individual steering wheel control switches. The following values should display depending on which switch is depressed.
* While rotating the individual scroll wheel control switches UP multiple times, the value of the Left Source Button or the Right Source Button parameter starts counting until a maximum value of 127 counts are shown. When the switch is released, the Left Source Button or the Right Source Button parameter restarts from 0.
* While rotating the individual scroll wheel control switches DOWN multiple times, the value of the Left Source Button or the Right Source Button parameter starts counting until a minimum value of -127 counts are shown. When the switch is released, the Left Source Button or the Right Source Button parameter restarts from 0.
Circuit/System Testing
1. Ignition OFF, disconnect the harness connector at the steering wheel switch assembly.
2. Test for less than 5 ohms between the low reference circuit terminal 5 and ground.
• If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the IPC.
3. Ignition ON, test for 4.8-5.2 volts between the signal circuit terminal 6 and ground.
• If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the IPC.
• If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the IPC.
4. Test for 4.8-5.2 volts between the signal circuit terminals listed below and ground.
* Right Steering Wheel Scroll 2 terminal 1.
* Right Steering Wheel Scroll 1 terminal 2.
* Left Steering Wheel Scroll 1 terminal 3.
* Left Steering Wheel Scroll 2 terminal 4.
• If less than the specified range, test the appropriate signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the IPC.
• If greater than the specified range, test the appropriate signal circuit for a short to voltage. If the circuit tests normal, replace the IPC.
5. If all circuits test normal, replace the steering wheel control switch assembly.
Component Testing
1. Ignition OFF, disconnect the harness connector at the steering wheel switch assembly.
2. Test for 0.5-O.L. ohms between the scroll wheel terminals listed below, while rotating each steering wheel scroll wheel several times through its full range of motion.
* right steering wheel scroll wheel terminal 1 and terminal 2.
* left steering wheel scroll wheel terminal 3 and terminal 4.
• If not within the specified range or is erratic, replace the steering wheel switch.
3. Test the resistance between the signal terminal 6 and the low reference terminal 5 while depressing the appropriate steering wheel controls switch button listed below.
• If not the specified value, replace the steering wheel switch.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* Steering Wheel Control Switch Assembly Replacement (Service and Repair)
* Control Module References (Programming and Relearning) for BCM replacement, setup, and programming