B2501

DTC B2501

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.



DTC Descriptor
DTC B2501 5A
- Horn Switch Stuck




Diagnostic Fault Information






Circuit/System Description

The right steering wheel control switch monitors the horn switch signal circuit, when the horn pad is pressed, the right steering wheel control switch detects the drop in the horn switch signal circuit and sends a serial data message to the underhood fuse block which commands the horn to sound.


Conditions for Running the DTC

When the output is actively being requested by steering wheel module.


Conditions for Setting the DTC

The steering wheel module detects a short to ground in the horn switch signal circuit or a stuck horn switch for greater than 60 seconds.


Action Taken When the DTC Sets

The horn will continuously sound until it is disconnected or when it overheats and becomes inoperative.


Conditions for Clearing the DTC

* The DTC clears when the fault is no longer detected.
* The current DTC will become history when the request for the output is removed.
* The history DTC will clear after 50 consecutive fault-free ignition cycles have occurred.



Reference Information
Schematic Reference

Horn Schematics ([1][2]Electrical Diagrams)
Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

Horns System Description and Operation (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, observe the scan tool Horn Relay Status parameter while pressing and releasing the horn pad, the reading should change from On to Off.


Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the horn switch.
2. Ignition ON, verify the scan tool Horn Relay Status parameter is Off.

• If not the specified parameter, test the signal circuit terminal for a short to ground. If the circuit tests normal, replace the right steering wheel control switch.

3. If all circuits test normal, replace the horn switch.



Repair Instructions

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

* Steering Wheel Horn Switch Replacement (Service and Repair)
* Control Module References (Programming and Relearning)for steering wheel module replacement, setup, and programming