C0156 code meaning
Right Front ABS Outlet Solenoid Circuit
What C0156 means
C0156 completes the Saab/GM group of four and is likewise absent from the accessible J2012 tables. Saab lists it as the right pressure-reduction valve for the 9-3/9-5 with Bosch 5.3 traction control and as the right pressure relief valve in the 9-5 ESP; GM's PIP5094 keyword list names the code, and AA1Car's GM-based table gives Right TCS Solenoid #2. Reading it as the right front outlet valve fits its task of releasing pressure from that circuit after a traction or ABS intervention. Saab's fault page ends, after the wiring and actuator checks, with replacing the control module, since the coils are tied to the electronic unit. Until then the car brakes normally but without ABS, TCS or ESP support.
C0156 at a glance
- Check engine lightUsually not
- Emissions testNot an emissions code
- Limp modePossible
- Repair difficultyHard
- Typical labor1 to 4 hours
- Clears after repairWhen cleared with a scanner
Symptoms of C0156
- ABS, brake and TCS/ESP OFF lamps on
- Wheels may lock under emergency braking
Common causes of C0156
- Most likelyOpen or shorted coil of the right pressure-reduction valve
- PossibleFault inside the control unit carrying the valve coils
- Less likelyMoisture or corrosion at the control unit connector
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
ABS outlet solenoidABS hydraulic unitABS control module
What each part of C0156 means
| C | Chassis system: brakes, ABS, steering and suspension. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 56 | The exact fault in that area. |
What to do next
- Note C0156 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about C0156
What does C0156 mean?
C0156 means "Right Front ABS Outlet Solenoid Circuit". C0156 completes the Saab/GM group of four and is likewise absent from the accessible J2012 tables. It is a generic code, so it means the same on every make.
Is it safe to drive with C0156?
Drive gently and only to a workshop. With C0156 the car can go into limp mode (reduced power) to protect itself.
Will C0156 fail an emissions test?
C0156 is not an emissions code, so on its own it usually does not fail an emissions test. Other stored codes or a lit check engine light still can.
How hard is C0156 to fix?
Difficulty: hard. A typical repair takes 1 to 4 hours of work. This is a job for a workshop.
Will C0156 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.