C0034
Left Front Wheel Speed Sensor No Signal
No pulses are received from the left front wheel speed sensor while other wheels report motion. The fault disables ABS and stability control.
- Check engine light: Not always
- Emissions related: No
- Repair difficulty: medium
Symptoms
- ABS warning light on
- ESC/stability control deactivated
- Possible reduced brake assist
- Speedometer may behave erratically
Common causes
Ordered by how often each turns out to be the cause.
- Sensor internally failedCommon
- Wiring open at suspension flexPossible
Parts involved
- Wheel Speed Sensor Fl
- Sensor Wiring
- Tone Ring
C0034 is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.