P2400 — EVAP Leak Detection Pump Control Circuit/Open
Low severityWhat it means
P2400 is stored when the engine control unit sees a fault involving the EVAP leak detection pump circuit. The leak detection pump pressurises the EVAP system so the control unit can test it for leaks; a circuit fault stops that test running. The “open” status means the control circuit is electrically broken — usually a cut wire, an unplugged connector or a failed driver.
Common symptoms
- The component does not respond to commands
- Usually only a check engine light
- EVAP monitor not completing
- Failed emissions inspection
Likely causes
- Open or broken wire in the control circuit
- Unplugged or corroded connector
- A failed leak detection pump
- A wiring, connector or fuse fault
What to check first
- Check circuit continuity and connector pins with the key off
- Command the pump with a scan tool and listen for it run
- Inspect the pump connector and wiring
Can you keep driving?
Safe to drive; it is an emissions fault, but the car will fail an emissions test until repaired.
Frequently asked questions
What is the most common cause of P2400?
The most likely cause is: Open or broken wire in the control circuit. Several other faults can set P2400 as well, so confirm the real cause with live data and the checks above before replacing any parts.
Can I just clear P2400 and keep driving?
Clearing P2400 with an OBD2 scanner turns the warning light off, but if the underlying fault has not been repaired the code will usually come back within a few drive cycles. Fix the cause first, then clear the code to confirm the repair worked.
How serious is P2400?
P2400 is a low-severity code. It rarely affects how the car drives, but it is still worth fixing so the engine runs efficiently and passes an emissions test.
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