Circuit Description
The steering wheel controls are momentary contact switches that connect a series of resistors so that each switch selection corresponds to a fixed resistance value. The body control module (BCM) determines which switch has been pressed by the voltage drop across the corresponding resistance value. The BCM supplies voltage to the steering wheel controls through the rear wiper/washer switch supply voltage circuit. The BCM monitors the switch voltage on the remote radio control signal circuit.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC B2815 Steering Wheel Controls Illegal Resistance Value
Conditions for Running the DTC
This test is run every 125 milliseconds.
Conditions for Setting the DTC
The BCM detects a switch voltage that is higher than normal.
Action Taken When the DTC Sets
The BCM will ignore the switch command.
Conditions for Clearing the MIL/DTC
| • | The DTC will become history if the BCM no longer detects a circuit malfunction. |
| • | The history DTC will clear after 100 fault free ignition cycles. |
| • | The DTC can be cleared with a scan tool. |
Test Description
The number below refers to the step number on the diagnostic table.
Step | Action | Values | Yes | No |
|---|---|---|---|---|
Schematic Reference: HVAC Schematics Connector End View Reference: HVAC Connector End Views | ||||
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information |
2 |
Does the scan tool indicate that the SWC Switch Voltage parameter is near the specified value? | 0 V | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems | Go to Step 3 |
Caution: Refer to SIR Caution in the Preface section. Does the scan tool indicate that the SWC Switch Voltage parameter is near the specified value? | 0 V | Go to Step 6 | Go to Step 4 | |
4 |
Does the scan tool indicate that the SWC Switch Voltage parameter is near the specified value? | 0 V | Go to Step 7 | Go to Step 5 |
5 | Test the signal circuit of the steering wheel controls for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 12 | Go to Step 8 |
6 | Inspect for poor connections at the harness connector of the left steering wheel control switch. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 12 | Go to Step 9 |
7 | Inspect for poor connections at the harness connector of the right steering wheel control switch. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 12 | Go to Step 10 |
8 | Inspect for poor connections at the harness connector of the BCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 12 | Go to Step 11 |
9 | Replace the left steering wheel control switch. Refer to Steering Wheel Control Switch Assembly Replacement in Steering Wheel and Column. Did you complete the replacement? | -- | Go to Step 12 | -- |
10 | Replace the right steering wheel control switch. Refer to Steering Wheel Control Switch Assembly Replacement in Steering Wheel and Column. Did you complete the replacement? | -- | Go to Step 12 | -- |
11 | Replace the BCM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming. Did you complete the replacement? | -- | Go to Step 12 | -- |
12 |
Does the DTC reset? | -- | Go to Step 2 | System OK |
