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Steering Wheel Controls Malfunction




Steering Wheel Controls Malfunction

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.

* Diagnostic Procedure Instructions Diagnostic Procedure Instructions 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 signal. The resistor ladder switch functions are 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. The scroll wheel switches provide a momentary pulse to the IPC to control volume, station presets, and change CD tracks.

Reference Information

Schematic Reference

Steering Wheel Secondary/Configurable Control Schematics Steering Wheel Secondary/Configurable Control Schematics

Connector End View Reference

Component Connector End Views Fuel Pump and Level Sensor Assembly

Description and Operation

Steering Wheel Controls Description and Operation Steering Wheel Controls

Electrical Information Reference

* Circuit Testing Circuit Testing

* Connector Repairs Connector Repairs

* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections

* Wiring Repairs Wiring Repairs

Scan Tool Reference

Control Module References Control Module References 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 and all vehicle systems OFF, disconnect the harness connector at the steering wheel switch assembly. It may take up to 2 minutes for all vehicle systems to power down.

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. Ignition OFF and all vehicle systems OFF. It may take up to 2 minutes for all vehicle systems to power down.

5. Test for less than 10 ohms between the steering wheel switch ground terminal 7 and ground.

If greater than the specified range, test the steering wheel switch ground for an open/high resistance. If the circuit tests normal, replace the steering wheel switch.

6. Ignition ON, 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.

7. 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 repair.

* Steering Wheel Control Switch Assembly Replacement Service and Repair

* Control Module References Control Module References for BCM replacement, setup, and programming