What does it mean?
C1139 is a Chassis (ABS, traction control, steering) fault code. It indicates: ABS Hydraulic Valve Power Relay Circuit Open . 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 illuminated shortly after start up
- No solenoid or relay noise during the ignition on self test
- ABS does not operate during hard braking, so wheels can lock
- Traction control, stability control and hill hold unavailable
- Fault sets again as soon as it is cleared
- Normal braking is retained but with no anti-lock support
Likely causes
- Open relay coil or burnt contacts in the valve power relay
- Blown fuse or fusible link feeding the valve block
- Broken wire or a terminal pushed out of the relay socket or module connector
- Corroded connector pins after water reached the modulator area
- Poor ground for the relay circuit, including a rusted body stud
- Harness damaged by rodents or by contact with a hot or sharp component
- Open relay driver output inside the ABS control module
How to fix it
- Check the ABS fuses and fusible links with a meter
- Inspect the relay socket for backed out terminals, corrosion and heat marks
- Measure the relay coil resistance out of circuit and replace it if it reads open
- Check continuity of the control wire from the module connector to the relay
- Verify the ground path for the circuit and clean the ground stud
- Repair the open in the harness, then command the relay with the scan tool to confirm
- Replace the hydraulic unit if the relay is integrated and confirmed open, then code and bleed