C0309Outlet Valve Rear Right Performance
- Generic OBD-II code · Chassis
- Can trigger limp mode
- How the car detects it
- C0309 is no part of any public J2012 table, and no manufacturer documents it as a valve code. GM does use it: it is among the keywords of PIP5094, and the GM code chart on AA1Car calls it Motor A/B Circuit High, a transfer case shift motor fault next to C0308 and C0310; that meaning rests on this single source. The title instead names the rear right outlet valve. It opens to let fluid out of the right rear caliper into the accumulator when that wheel tends to lock and stays shut otherwise. Saab's 9-5 checks each valve with a 20 ms pulse at every ignition-on, and a fault turns ABS, traction and stability control off. A valve stuck open would keep the right rear wheel from building pressure.
- What you may notice
- ABS and stability control warning lamps on
- Weak braking at the right rear wheel
- Likely causes
- PossibleRear right outlet valve not closing fully
- PossibleValve coil or brake module driver faulty
- RareOn GM 4WD trucks, transfer case motor circuit shorted to voltage (GM meaning of the number)
- Repair
- Hard · Usually a job for a workshop.Typical cost: €150 – €1,500
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.