What does it mean?
C1105 is a Chassis (ABS, traction control, steering) fault code. It indicates: ABS RR Wheel Speed Sensor 2 .
Symptoms
- ABS and stability control lamps on together
- Stability control cuts in unexpectedly on a straight, dry road
- Traction control and hill hold functions switched off
- ABS activates briefly at walking pace as the vehicle stops
- Fault appears only after driving a certain distance or over rough surfaces
- Live data shows the right rear reading zero or erratic against three steady wheels
Likely causes
- Corroded sensor connector in the rear wheel arch, a common area for road salt and water
- Chafed or broken sensor wire where the harness crosses the rear suspension arm
- Rusted or damaged tone ring, often built into the rear bearing or drive shaft
- Debris or a magnetised deposit on the sensor tip
- Worn rear wheel bearing allowing the air gap to change while driving
- Internal sensor failure or a loose sensor mounting bolt
- Wrong tyre size or a temporary spare fitted on that corner distorting the signal
How to fix it
- Watch all four wheel speeds in live data during a road test
- Inspect the rear sensor connector for water, corrosion and green terminals
- Follow the harness along the rear axle or suspension arm and look for chafing and stretch marks
- Remove the sensor and clean the tip, then inspect the tone ring through the bearing opening
- Measure sensor resistance or signal output and compare with the opposite side
- Check rear bearing play and confirm the sensor bolt is tight and the sensor seated fully
- Replace the sensor, bearing or tone ring as the tests indicate, then clear and road test