C0317Compressor Relay Circuit
- Generic OBD-II code · Chassis
- Can trigger limp mode
- How the car detects it
- C0317 is publicly undocumented: it is missing from every publicly available J2012 list, from GM's keyword bulletin PIP5094 and from the whole NHTSA bulletin index. What follows describes only the part named in the title. On air or self-levelling suspension a relay carries the heavy compressor current and is energised by the suspension module. Land Rover ships the compressor relay together with the replacement compressor for the 2010 Range Rover, whose compressor could fail by running too long. Audi has technicians open relay J403 of the self-levelling compressor on A6 and Q7 models and judge its contacts: burnt contacts mean compressor and relay are both renewed. Volvo checks fuse and relay before it blames the compressor. A circuit fault here leaves the vehicle unable to raise or hold its ride height.
- What you may notice
- Suspension warning or air suspension fault message
- Vehicle sits low and does not rise
- Compressor runs constantly or never starts
- Likely causes
- LikelyRelay contacts burnt or welded by a compressor drawing too much current
- PossibleOpen or shorted control line between suspension module and relay coil
- PossibleWorn or seized compressor overloading the relay
- RareBlown compressor fuse or corroded relay socket
- Repair
- Medium · Often possible to do yourself.Typical cost: €20 – €1,200
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.