What it means
The module detects an open circuit or missing signal from the right-rear wheel-speed sensor. The fault may be in the sensor, wiring, or connection.
At a glance
- Usually lights the ABS or stability-control warning light
- The engine or gearbox may go into limp mode
How it works
The ABS module relies on the right-rear wheel-speed sensor to report that wheel’s rotation. It sets C0512 when the right-rear circuit is open or the module receives no usable signal, which can result from a disconnected or broken circuit as well as a failed sensor.
Common causes
Most likely first.
- Broken or disconnected wiring
- Loose or corroded connector
- Failed wheel-speed sensor
- Damaged tone ring or encoder
Symptoms
- ABS warning light on
- ESC/stability control deactivated
- Possible reduced brake assist
- Speedometer may behave erratically
How to diagnose it
- Read freeze-frame data and compare live right-rear speed with the other wheels to confirm whether the reading is absent.
- Inspect the right-rear sensor connector for disconnection, corrosion, loose terminals, or physical damage.
- Trace the right-rear sensor wiring for a break, chafe, or damage where it moves with the suspension.
- Check continuity and shorts in the right-rear sensor circuit using the vehicle wiring diagram and manufacturer’s specifications.
- If the circuit is intact, test the right-rear sensor and inspect its tone ring or encoder for damage or contamination.
Common fixes
- Reconnect or clean the right-rear sensor connector and repair damaged terminals.
- Repair a broken or chafed right-rear sensor wire.
- Replace a failed right-rear wheel-speed sensor.
- Repair or replace a damaged right-rear tone ring or encoder.
Can I keep driving?
The basic hydraulic brakes may still work, but ABS and stability control may be disabled and brake assist may be reduced. Drive carefully, increase following distance, and avoid conditions that require emergency braking until repaired.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.