Steering Wheel Controls Inoperative
Steering Wheel Controls Inoperative
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 radio supplies voltage to the steering wheel control momentary contact switches and monitors the return signal. Each switch is associated to a set resistance value and when pressed a specific voltage drops across the resistor unique to the switch. The radio identifies the switch selected and activates the feature. Otherwise the radio sends a serial data message to the component controlled by the switch activating the feature.
Diagnostic Aids
* Before diagnosis of the steering wheel controls, ensure the primary controls of the associated component are functioning properly.
* If a single switch function is inoperative, test the suspect switch. Refer to component testing.
* A poor connection at the right switch could cause all the switches to be inoperative.
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)
Circuit/System Testing
Important: It is recommended that Component Testing be performed before Circuit Testing when diagnosing steering wheel controls.
Caution: Refer to SIR Caution (SIR Caution).
1. Ignition OFF, disconnect the harness connector at the right steering wheel control switch.
2. Ignition ON, radio ON, test for 6.5-9.0 volts between the ignition circuit terminal 5 and ground.
• If less than the specified value, test the circuit for a short to ground or open/high resistance. If circuit tests normal, replace the radio.
• If greater than the specified value, test the circuit for short to voltage. If circuit tests normal, replace the radio.
3. Test for 6.5-9.0 volts between the ignition circuit terminal 5 and the signal circuit terminal 1.
• If less than the specified value, test the circuit for an open/high resistance. If the circuit tests normal, replace the radio.
• If greater than the specified value, test the circuit for a short to voltage. If the circuit tests normal, replace the radio.
4. Install a 3A fused jumper wire between the ignition circuit terminal 5 and the ignition circuit terminal 2.
5. Disconnect the harness connector at the left steering wheel control switch.
6. Test for 6.5-9.0 volts between the ignition circuit terminal 4 and ground.
• If less than the specified value, test the circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the radio.
• If greater than the specified value, test the circuit for short to voltage. If the circuit tests normal, replace the radio.
7. Test for 6.5-9.0 volts from the ignition circuit terminal 4 and the signal circuit terminal 1.
• If less than the specified value, test the circuit for an open/high resistance. If the circuit tests normal, replace the radio.
• If greater than the specified value, test the circuit for a short to voltage. If the circuit tests normal, replace the radio.
8. Ignition OFF, disconnect the X1 harness connector at the radio.
9. Test for infinite resistance between the signal circuit terminal A7 and ground.
• If less than the specified value, test the signal circuit for a short to ground. If the circuit tests normal, replace the radio.
10. If all circuits test normal, test or replace the steering wheel control switch.
Component Testing
Caution: Refer to SIR Caution (SIR Caution).
1. Ignition OFF, disconnect the harness connector at the steering wheel control switches.
2. Test the right switch for less than 2,400 ohms of resistance between the ignition terminal 5 and the ignition terminal 2.
• If greater than the specified value, replace the steering wheel control switch.
3. Test for infinite resistance between the ignition terminal 5 and the signal terminal 1 with the switch in the open position.
• If less than the specified value, replace the steering wheel control switch.
4. Test for less than 2,400 ohms of resistance between the ignition terminal 5 and the signal terminal 1 with the switch in the closed position.
• If greater than the specified value, replace the steering wheel control switch.
5. Test the left switch for infinite resistance between the ignition terminal 4 and the signal terminal 1 with the switch in the open position.
• If greater than the specified value, replace the steering wheel control switch.
6. Test for less than 12000 ohms of resistance between the ignition terminal 4 and the signal terminal 1 with the switch in the closed position.
• If greater than the specified value, replace the steering wheel control 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 Radio replacement, setup, and programming