C1238
ABS Hydraulic Pressure Differential Switch Input Circuit Failure
Severity
⚠️ MediumCan you drive?
Do not drive — repair immediately
Approx. repair cost
$56–167 (est.)
Symptoms
- ABS light is on
- ABS does not activate when braking
- Uneven braking on slippery surfaces
Causes
- Malfunction of the differential pressure sensor
- Open or shorted wiring harness
- Problems with sensor connectors
- ABS control unit malfunction
How to Fix
- Diagnosing the Sensor Circuit Using a Multimeter
- Checking the resistance and voltage on the sensor
- Inspect the wiring harness for damage
- Replacing the sensor or repairing the circuit if necessary
- Resetting errors and testing the system