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4-Spoke




DTC B3608 (4-Spoke)

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.

DTC Descriptor
DTC B3608 01
- Steering Wheel Control Entertainment Output Signal Circuit Short to Battery

Diagnostic Fault Information






Circuit/System Description

The radio supplies voltage to the audio steering wheel control switches and monitors the return signal. Each switch state is associated to a set resistance value and when pressed a specific voltage drop occurs across the resistor unique to the switch. The radio identifies the switch selection and activates the feature.

Conditions for Running the DTC

* Battery voltage is between 9-16 volts
* The ignition is ON.

Conditions for Setting the DTC

The radio detects a short to voltage in the steering wheel control signal circuit.

Action Taken When the DTC Sets

The steering wheel control switch functions are inoperative.

Conditions for Clearing the DTC

* The conditions for setting the DTC are no longer present.
* A history DTC clears after 100 malfunction-free ignition cycles.

Diagnostic Aids

Before diagnosis of the steering wheel controls, ensure the primary controls of the associated component are functioning properly.

Reference Information
Schematic Reference

* Steering Wheel Secondary/Configurable Control Schematics Steering Wheel Secondary/Configurable Control Schematics
* Radio/Navigation System Schematics Radio/Navigation System Schematics

Connector End View Reference

Component Connector End Views Connector End Views By Name
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 Programming and Relearning for scan tool information

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the left and right steering wheel control switches.
2. Ignition ON, radio ON, test for 9.8-10.2 volts between the voltage reference circuit terminal 1 and ground.

If greater than the specified range, test the voltage reference circuit for a short to voltage. If the circuit tests normal, replace the radio.
If less than the specified range, test the voltage reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the radio.

3. Test for greater than 9 volts between the voltage reference circuit terminal 5 and the signal circuit terminal 4.

If less than the specified range, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the radio.

4. Ignition OFF, disconnect the X1 harness connector at the radio.
5. Test for infinite resistance between the signal circuit terminal 1 and ground.

If less than the specified value, test the signal circuit for a short to ground.

6. Ignition ON, test for less than 1 volt between ground and the voltage reference circuit terminal 1 at the left steering wheel control switch.

If greater than the specified range, test the voltage reference circuit for a short to voltage.

7. Ignition ON, test for infinite resistance between ground and the voltage reference circuit terminal 1 at the left steering wheel control switch.

If not the specified value, test the voltage reference circuit for a short to ground.

8. Test for less than 1 ohm between the voltage reference circuit terminal 1 at the left steering wheel control switch and the voltage reference circuit terminal 5 at the right steering wheel control switch.

If greater than the specified range, test the voltage reference circuit for a an open/high resistance.

9. If all circuits test normal, test or replace the left or right steering wheel control switch.

Component Testing

1. Disconnect the harness connector at the right or left steering wheel control switch.
2. Connect a DMM between terminal 1 and terminal 4 of either the left or right steering wheel control switch.

If any of the resistance measurements for the individual switches are not within the specified resistance values, replace the right steering wheel control switch.










Repair Instructions

Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.

* Steering Wheel Control Switch Assembly Replacement (Cruise Control and Radio Switch) Service and Repair
* Control Module References Programming and Relearning for radio replacement, setup, and programming