What does it mean?
C1416 is a Chassis (ABS, traction control, steering) fault code. It indicates: Rear Speed Sensor LH Output Malfunction .
Symptoms
- ABS and stability control lamps illuminate and both systems switch off
- Traction control and hill hold stop working
- On some vehicles trip computer values or transmission behaviour change because the rear speed input is missing
- Unexpected short ABS activation at walking pace before the code becomes permanent
- No change in normal braking feel outside ABS events
Likely causes
- Metal debris or brake dust bridging the sensor tip and the tone ring at the rear hub
- Damaged, rusted or spun tone ring pressed onto the rear hub or axle shaft
- Chafed or broken sensor wire where the harness follows the rear axle and suspension arms
- Corroded connector behind the rear wheel arch, often after exposure to winter road salt
- Rear wheel bearing play or a loose sensor bolt increasing the air gap
- Internally failed sensor element
- Damaged module input circuit or a poor ground shared by the rear sensors
How to fix it
- Check freeze frame data to see at what speed the signal was lost
- Compare all four wheel speed readings on live data during a slow drive; the left rear will read zero or jump around
- Inspect the sensor, tone ring and rear harness routing for debris, rust and chafe points
- Clean the sensor and ring, then refit with the correct torque and check the air gap
- Measure the sensor resistance or output at the connector and test the circuit for an open or a short to ground
- Wiggle the harness and connector while monitoring the live value to catch an intermittent fault
- Replace the sensor, tone ring or hub assembly as required, then clear the codes and verify with a road test