BMW DTC C120B – Wheel Speed Sensor Rear/Right Circuit High
DTC C120B meaning on BMW
DTC C120B on a BMW refers to an issue with the Wheel Speed Sensor Rear/Right Circuit being detected as high. This means that the sensor responsible for monitoring the speed of the right rear wheel is reporting a signal that is higher than the expected range.
BMW DTC C120B symptoms
Symptoms of DTC C120B on a BMW may include:
- ABS warning light illuminated on the dashboard
- Traction control system malfunction
- Unusual braking behavior, such as ABS activation under normal braking conditions
BMW DTC C120B causes
Common causes of DTC C120B on a BMW include:
- Faulty wheel speed sensor
- Corroded or damaged sensor wiring
- Poor electrical connection at the sensor
- Issues with the ABS control module
BMW DTC C120B seriousness
DTC C120B should be taken seriously as it can affect the proper functioning of the ABS and traction control systems. Driving with this fault unresolved may compromise the vehicle’s stability and safety, especially during braking and cornering maneuvers.
How to diagnose DTC C120B on BMW
To diagnose DTC C120B on a BMW, you can follow these steps:
- Use a diagnostic scanner to retrieve the fault codes from the ABS system
- Inspect the right rear wheel speed sensor and its wiring for any visible damage or corrosion
- Check the sensor’s resistance and signal output using a multimeter
- Perform a visual inspection of the ABS control module and related components
How to fix DTC C120B on BMW
To fix DTC C120B on a BMW, you can try the following:
- Replace the faulty wheel speed sensor
- Repair or replace any damaged wiring or connectors associated with the sensor
- Clean any corrosion from the sensor mounting area
- If necessary, replace the ABS control module
How to erase DTC C120B on BMW
To erase DTC C120B on a BMW, you can use a diagnostic scanner to clear the fault codes stored in the ABS system’s memory. After performing the necessary repairs and ensuring the issue is resolved, you can reset the system to remove the fault code and turn off the warning light on the dashboard.
Recommended tools & DTC Scanners for BMW
Best Diagnostic App for modern BMWs: BimmerLink
Recommended Bluetooth adapter for Bimmerlink: OBDLink CX
Cable adapter for Bimmerlink: Enet Cable USB Type C
For older BMWs we recommend: Autel AutoLink AL319 (2024 version)
Easy-to-use Multimeter for reliable diagnostics: AstroAI Auto-ranging Multimeter
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