Failed compressor relay; Open or shorted wiring in the compressor relay control circuit; Corroded or loose electrical connectors at the relay or ABS module; Faulty ABS control module (internal driver failure); Blown fuse or poor ground connection for the relay circuit; Damaged compressor motor causing excessive current draw that stresses the relay circuit

DTC codes / C03xx · Brakes, steering and suspension / C0317

C0317Compressor Relay Circuit

Q: What does code C0317 mean?

Compressor Relay Circuit. C0317 indicates that the antilock brake system (ABS) control module has detected an electrical fault in the circuit that powers the compressor relay, which is used to drive the air suspension compressor on vehicles so equipped. The module monitors the relay control circuit for open circuits, short circuits, or abnormal voltage levels and sets this code when the expected current or voltage is not present.

C0317 indicates that the antilock brake system (ABS) control module has detected an electrical fault in the circuit that powers the compressor relay, which is used to drive the air suspension compressor on vehicles so equipped. The module monitors the relay control circuit for open circuits, short circuits, or abnormal voltage levels and sets this code when the expected current or voltage is not present.

SystemChassis

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyIntermediate

AreaBrakes, steering and suspension

Symptoms you may notice

ABS warning light illuminated on the dashboard
Air suspension compressor may not run, causing the vehicle to sit low or level unevenly
Ride height may be stuck at one level or the suspension may not adjust
Often no symptoms besides the warning light, especially if the compressor is not needed immediately
In some cases, other suspension-related warning messages may appear

Common causes, most likely first

Failed compressor relay
Open or shorted wiring in the compressor relay control circuit
Corroded or loose electrical connectors at the relay or ABS module
Faulty ABS control module (internal driver failure)
Blown fuse or poor ground connection for the relay circuit
Damaged compressor motor causing excessive current draw that stresses the relay circuit

How to diagnose and fix it

Verify the code with a scan tool and check for any related ABS or suspension codes
Inspect the compressor relay and its socket for corrosion, loose pins, or signs of overheating
Test the relay by swapping it with a known-good identical relay and clearing the code
Check the fuse and ground connections for the compressor relay circuit
Perform a voltage drop test on the relay control circuit to identify high resistance or open circuits
If the circuit tests good, test the compressor motor for excessive current draw or short
If all external components test good, diagnose the ABS module driver circuit or replace the module as needed

Relay circuit faults often misdiagnosed

A failed compressor relay is the most common cause, but technicians often replace the ABS module first without testing the relay and wiring.
The code can be set by a weak battery or charging system issue that causes low voltage during relay activation, so always check battery health.
Corrosion inside the relay socket is a frequent hidden cause, especially on vehicles driven in wet or salty conditions.
The compressor relay may be shared with other systems, so a fault can cause unrelated symptoms like intermittent suspension operation.
After repairs, the code may require several drive cycles to clear, and some vehicles need a relearn procedure for the suspension system.

Can I keep driving with C0317?

You can usually drive the vehicle with this code, but the air suspension may not function correctly, leading to poor ride quality or reduced ground clearance. Avoid heavy loads or rough roads until repaired, and address the issue promptly to prevent compressor damage.

Tools that help

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Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.