C0237Loss of Speed Sensor Signal Front Left
- Generic OBD-II code · Chassis
- Can trigger limp mode
- Needs a drive cycle to confirm a fix
- How the car detects it
- The publicly available J2012 tables skip C0237. GM lists the number in PIP5094, and AA1Car's GM-based code table reads it as Rear Wheel Speed Signal Erratic, so GM's use concerns the rear axle, not the front left wheel of the title. Other makers code a lost front left signal differently: the Saab 9-5 records an open or shorted front left sensor as C1372 and a mechanical or functional fault as C1371, switching ABS, TCS and ESP off. A total loss means no pulses reach the module although the other wheels turn; typical reasons are a cable torn at the steering knuckle, a sensor pushed away from its 29-tooth ring or a damaged connector. HELLA advises checking supply and signal with a meter and oscilloscope before a new sensor is fitted.
- What you may notice
- ABS, traction and stability lamps on
- No ABS; speedometer may misread if it uses this wheel
- Likely causes
- LikelyBroken sensor cable or damaged connector at the front left wheel
- PossibleSensor failed or pushed out of position after suspension work
- RareTone ring damaged or missing after drive shaft or hub replacement
- Repair
- Medium · Often possible to do yourself.Typical cost: €40 – €300
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.