What does it mean?
C1112 is a Chassis (ABS, traction control, steering) fault code. It indicates: Sensor source voltage .
Symptoms
- Several sensor codes stored at the same time, all fed by the same reference
- Multiple warning lamps illuminated together
- Live data shows sensors reading at the extreme end of their scale or stuck at one value
- Systems that rely on those sensors are switched off
- The fault can be intermittent and triggered by bumps, washing or damp weather
- Codes return quickly after being cleared
Likely causes
- One sensor on the shared reference line failed internally and is dragging the supply down
- Reference wire chafed to ground or to a battery feed inside the harness
- Water or corrosion in a sensor connector bridging the reference pin to another pin
- Broken or high resistance reference wire, or a terminal backed out of its housing
- Poor module ground shifting the reference the module measures against
- Failed internal voltage regulator inside the control module
How to fix it
- Measure the reference voltage at each sensor connector with the key on
- Unplug sensors one at a time and watch whether the reference recovers, which identifies the shorted one
- Check the reference wire for continuity and for a short to ground and to battery voltage
- Inspect every connector on that circuit for moisture, corrosion and pushed back terminals
- Clean and tighten the module ground point
- Repair the harness or replace the sensor that loads the circuit
- Replace the control module only when the reference is still out of range with all sensors unplugged