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P2400

EVAP System Leak Detection Pump Control Circuit/Open

Evaporative emissions (EVAP) Generic OBD-II Low

What it means

P2400 means the ECM detected an open in the control circuit for the EVAP leak detection pump — the pump used to test the fuel-vapor system for leaks. It's an electrical fault (open wiring, a failed pump, or a bad connector), not a fuel leak, so the car drives normally. It mainly prevents the EVAP monitor from completing until it's fixed.

Low

Can I keep driving? Yes — this is an emissions-monitoring fault with no effect on how the car drives; just fix it before an emissions test.

Real-world scan data

Seen in
42
scans in the past year
Found in
<0.1%
of scans
<0.1%
of scans that found faults

Figures reflect only diagnostic scans recorded through our own apps and tools. Cars are typically scanned because a symptom or warning light prompted it, so these counts describe our scan records — not the incidence of faults in any model, and not the quality, reliability, or safety of any vehicle. No comparison between manufacturers or models is implied. All trademarks belong to their respective owners; no affiliation or endorsement is implied.

Common symptoms

What you'll notice

Common causes

Most likely first

  1. Open circuit in the leak-detection pump control wiring
  2. Faulty EVAP leak detection pump
  3. Corroded or loose connector at the pump
  4. Blown fuse feeding the pump circuit
  5. ECM driver fault (less common)

How to diagnose & fix

Work through it in order

  1. Read freeze-frame data to see when the fault set.
  2. Check the leak-detection pump connector and control wiring for an open.
  3. Verify power and ground to the pump and check related fuses.
  4. Test the pump solenoid's resistance against spec.
  5. Replace the leak detection pump if faulty, then clear and re-test.

FAQ

Quick answers

Is it safe to drive with P2400?+
Yes — it's purely an emissions-system circuit fault and won't affect drivability. Repair it before an emissions test so the EVAP monitor can run.
Can I just clear P2400?+
It returns until the open circuit or faulty pump is repaired, because the ECM re-checks the circuit each drive cycle.

Related codes

Read & clear P2400 yourself

Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.

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Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX