What does it mean?
C1193 is a Chassis (ABS, traction control, steering) fault code. It indicates: ABS Hydraulic Valve Power Relay Circuit Short to Ground . This is a standardised OBD-II code. The technical definition is the same regardless of the make or model of vehicle, although specific causes and symptoms can vary between vehicles.
Symptoms
- ABS and stability control lamps on continuously from the moment the ignition is switched on
- ABS does not operate: the pedal never pulses and the wheels can lock during hard braking
- ABS fuse blowing again after replacement, or a rapid chattering noise from the relay box
- Hill-start assist and electronic brake force distribution stop working, sometimes with the red brake lamp
- The problem may appear only after heavy rain or after driving through deep water
Likely causes
- Wire rubbed through against a sharp body edge, a bracket or the hydraulic unit housing
- Standing water or salt inside the relay and fuse box creating a path to the vehicle body
- Relay with an internal short between its winding and metal case
- Harness trapped or crushed when a component was refitted after earlier repair work
- Corroded pins inside the ABS module connector allowing a terminal to touch the metal shield
- Damage low in the engine bay from stone chips, road salt or rodents
- ABS module low side driver failed short, holding the circuit at ground
How to fix it
- Check the ABS fuses first; the fuse that failed points straight to the branch of the circuit that is shorted
- Read every stored chassis code — a whole group of valve and relay codes together indicates a common circuit fault
- Open and dry the relay and fuse box, then inspect for water tracks, corrosion and burnt terminals
- With the relay removed and the module unplugged, measure resistance from the relay control terminal to ground; a near zero reading confirms the short
- Unwrap the harness from the fuse box to the hydraulic unit and inspect every clip, bracket and grommet for chafe
- Bench test the relay for a short between winding and case, and replace it if it fails
- Repair the wiring with soldered and sealed joints, reroute it away from the damage point, then clear codes and verify the self-test runs