C0840
Air Suspension Solenoid Valve Circuit
One of the level control solenoid valves reports an electrical fault. The corresponding axle cannot be levelled.
One of the level control solenoid valves reports an electrical fault. The corresponding axle cannot be levelled.
Common causes
- high
Solenoid coil open
One of the most commonly reported causes for this code — check this first.
Typical part cost: $220-990
- medium
Connector water damage
A plausible cause — test and verify before replacing parts.
Typical part cost: $220-990
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First things to check
- 1Confirm the code with a scan tool and check for additional related codes.
- 2Inspect the relevant sensors, wiring, and connectors for damage or corrosion.
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Related codes
See related trouble codes
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Frequently asked questions
What does C0840 mean?
C0840 means "Air Suspension Solenoid Valve Circuit". It is a generic OBD-II code that points to a fault in the chassis.
What are the most common causes of C0840?
solenoid coil open; connector water damage — these are the most commonly reported causes. Verify with a proper diagnosis before replacing parts, or use the Wrenchify app for a vehicle-specific diagnosis.
Can I keep driving with this code?
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical. Use the Wrenchify app for a full diagnosis specific to your vehicle.
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