C0305Inlet Valve Rear Left Performance
- Generic OBD-II code · Chassis
- Can trigger limp mode
- How the car detects it
- C0305 is missing from the published J2012 lists and is not described by any maker as an ABS valve code. GM does use it: PIP5094 lists the number, and AA1Car's GM table calls it Front Speed Sensor Malfunction, the partner of C0300 in the block before the transfer case motor codes. The title refers to the rear left inlet valve. Besides ABS work, the rear inlet valves carry the electronic brake force split: on the 2011 Saab 9-5 the TRW module lowers rear pressure by cycling the rear valves instead of using a mechanical proportioning valve, and it also uses the valves to hold pressure for hill start assist. A sluggish rear left inlet valve can let that wheel lock early or brake too little, and the module then disables ABS and stability control.
- What you may notice
- ABS and brake warning lamps on
- Rear wheel locking early or hill start assist unavailable
- Likely causes
- PossibleRear left inlet valve sticking from contaminated fluid
- PossibleValve coil or brake module driver defective
- RareOn GM 4WD trucks, front speed sensor fault in the transfer case system (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.