C004ABrake Lining Wear Sensor
- Generic OBD-II code · Chassis
- How the car detects it
- Covers the brake lining (pad) wear sensor circuit, which warns the driver when friction material is worn to its limit. Electronic wear sensors use a loop embedded in the pad that the disc contacts and opens, or a wear-indicator circuit, as the lining wears down; the module reports pad wear and may store this code for an open, shorted or implausible sensor circuit as well as for a genuine worn-pad signal. It is an advisory function rather than a safety-critical control loss: braking and ABS continue, but the driver is told to inspect or replace the pads. The code can appear after pad replacement if the sensor was not renewed or reconnected. Delphi describes both the single loop and two-stage sensors with two resistor circuits. No manufacturer documents this code publicly.
- What you may notice
- Brake pad wear warning message
- Warning lamp on
- Possible squeal from a mechanical indicator
- Likely causes
- LikelyBrake pads worn to the sensor limit
- PossibleOpen or shorted wear sensor circuit
- RareSensor not renewed after pad change
- Repair
- Easy · Often possible to do yourself.Typical cost: €20 – €350
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.