What does it mean?
C1414 is a Chassis (ABS, traction control, steering) fault code. It indicates: Front Speed Sensor LH Output Malfunction .
Symptoms
- ABS and traction/stability control warning lamps stay on
- ABS and stability control shut down while normal hydraulic braking remains available
- Speedometer may drop to zero or read erratically on vehicles that use this sensor for road speed
- Hill start assist, cruise control or auto hold refuse to work
- Before the code latches, ABS can activate briefly at very low speed with an unexpected pedal pulse
Likely causes
- Brake dust, metal filings or mud packed on the sensor tip or tone ring, distorting the signal
- Cracked, rusted or damaged tone (reluctor) ring on the hub or driveshaft joint
- Chafed, broken or corroded wiring where the sensor harness runs along the strut and wheel arch
- Water and corrosion inside the sensor connector, giving intermittent high resistance
- Excessive wheel bearing play or an incorrectly seated sensor, opening up the air gap
- Internal failure of the sensor element, such as an open or shorted winding
- Rarely, a damaged input circuit inside the ABS/traction control module
How to fix it
- Read freeze frame data and note whether the fault is current or historic
- Compare all four wheel speed values on live data while driving slowly; the left front will drop out or read zero
- Inspect the left front sensor, tone ring and harness for debris, cracks, rust and chafing
- Clean the sensor tip and ring, then check the air gap and the mounting bolt torque
- Measure sensor resistance or output at the connector and test the circuit for an open or a short to ground
- Verify supply voltage and ground on active (Hall) type sensors, and wiggle test the connector while watching live data
- Replace the sensor, tone ring or hub bearing as the tests indicate, clear the code and road test to confirm