What does it mean?
C1232 is a Chassis (ABS, traction control, steering) fault code. It indicates: Drive Test: Pressure Sensor .
Symptoms
- ABS and stability lamps on, usually after a road test rather than immediately
- Stability control, hill-hold and brake assist unavailable
- Brake pedal feel different, softer or longer than normal
- ABS engaging earlier or later than expected during firm braking
- Fault returns each time the vehicle is driven and braked, then clears on key off
- One wheel or corner running hot when a brake is dragging
Likely causes
- Sensor zero point not learned after brake, hydraulic unit or sensor work
- Air left in the brake system after bleeding, so pressure does not rise as expected for the pedal effort
- Sensor drifted with age and reads a pressure offset with the pedal released
- Corroded connector or high resistance in the signal, reference or ground wire
- Residual pressure from a dragging caliper or a swollen flexible hose acting as a restriction
- Master cylinder bypassing internally, so pressure builds slowly
- Two pressure sensors on the same circuit disagreeing with each other
How to fix it
- Bleed the brake system properly and confirm a firm, high pedal before any electronic diagnosis
- Read the pressure sensor value with the pedal released; it should be at or near zero
- Press the pedal steadily and check the value rises smoothly and in proportion, and compare with a second sensor if fitted
- Check the reference voltage and ground at the sensor connector and inspect for corrosion or fluid ingress
- Check for dragging brakes and collapsed flexible hoses holding residual pressure
- Carry out the sensor zero point learn procedure and repeat the specified drive test
- Replace the sensor, or the hydraulic unit where the sensor is integrated, if the reading stays implausible