OBD-II reference

All 9.533 generic OBD-II codes, explained in detail.

Causes, inspection steps and sources — a comprehensive DIY archive. Created and maintained with love for the detail. Good luck and have fun!

Chassis generic / SAE

C0317

Compressor Relay Circuit

The air suspension control module has detected a circuit fault on the compressor relay output — typically open circuit, short to ground or short to power. Self-levelling is disabled and the vehicle may sit lower than normal.

SystemChassis
Typegeneric / SAE
GroupC0
Range / number3 / 17

Possible causes

  • Compressor relay failed (stuck or open) high
  • Compressor motor shorted, dragging supply down medium
  • Relay wiring or connector fault low

Symptoms

  • ABS warning light on
  • ESC/stability control deactivated
  • Possible reduced brake assist
  • Speedometer may behave erratically

Inspection / repair

  • Difficulty: medium
  • DIY: possible
  • Estimated cost: 80–700 €
  • Estimated time: 0.5–3 h
  • Component: compressor relay
  • Component: air compressor
  • Component: air suspension module
  • Component: relay wiring

Sources

References

How to read OBD-II codes

The first letter names the vehicle system, the second digit distinguishes generic from manufacturer-specific, the remaining digits group fault area and number.

PPowertrain: engine, transmission, emissions
BBody: chassis trim, comfort, interior
CChassis: suspension, brakes, steering
UNetwork: CAN, control modules, communication