Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
| • | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
| • | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
DTC Descriptor
DTC B2501 5A: Horn Switch StuckDiagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
Horn Switch Signal | B2501 5A | 2 | 2 | -- |
Horn Control | 2 | 2 | 1 | -- |
Horn Switch Ground | -- | 2 | 2 | -- |
Horn Ground | -- | 2 | 2 | -- |
1. Horn Always On 2. Horn Inoperative | ||||
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
Connector End View Reference
Description and Operation
Horns System Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References 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
- Ignition OFF, disconnect the harness connector at the right steering wheel control switch.
- Test for infinite resistance between the signal circuit terminal 2 and the low reference circuit terminal 1.
- Ignition ON, verify the scan tool Horn Relay Status parameter is Off.
- If all circuits test normal, replace the horn switch.
| ⇒ | If not the specified value, test the signal circuit for a short to ground. If the circuit tests normal, check for a sticking horn switch. |
| ⇒ | If not the specified value, replace the right steering wheel control switch. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for steering wheel module replacement, setup, and programming |
