C0235Wheel Speed Sensor Signal Erratic
- Generic OBD-II code · Chassis
- Can trigger limp mode
- Needs a drive cycle to confirm a fix
- How the car detects it
- C0235 does not show up in the publicly available J2012 lists. GM's bulletin PIP5094 names the number among chassis codes for cars and light trucks up to 2014, and AA1Car's GM-based ABS table renders it as Rear Wheel Speed Signal Circuit Open; an erratic-signal meaning is not documented by any maker. Taken by its title, the code concerns a speed signal that jumps or briefly drops out while the wheel turns steadily. HELLA's workshop guide names broken wires, internal shorts, heavy dirt and a growing air gap as the usual reasons, with pseudo control interventions or locking wheels as symptoms, and recommends comparing the wheel signals in live data and on a scope. Bosch's Hall sensors turn the encoder field into square current pulses, so a loose plug shows as missing pulses.
- What you may notice
- ABS lamp comes and goes
- Pulsing pedal or ABS intervention at low speed without reason
- Likely causes
- LikelyIntermittent wire break or loose connector, often at moving harness sections
- PossibleDirt, rust or metal debris on the sensor, enlarged air gap
- RareWheel bearing play letting the encoder wobble
- Repair
- Medium · Often possible to do yourself.Typical cost: €30 – €300
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.