P2401EVAP System Leak Detection Pump Control Circuit Low
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Needs a drive cycle to confirm a fix
- How the car detects it
- P2401 means the control line of the leak detection pump is pulled to ground level, usually by chafed insulation touching the body or by an internal pump fault. GM's 2016 Volt table checks the low-side driver while it is switched off; a near-zero impedance of about 0.5 Ohm to controller ground counts as a short, and 20 of 25 samples of 250 ms set a Type B code over two trips. VW's 2014 Golf and Touareg data books use a signal below about 2.15-3.26 V, depending on engine. Land Rover's SSM71298 (LR4, Range Rover Sport) and Subaru's ELCM bulletins also list P2401, Land Rover pointing to a defect inside the DMTL pump when the wiring checks out. Unlike P2400 the circuit is intact but shorted; the leak test is skipped while driving stays normal.
- What you may notice
- Check engine light
- Leak test not completed, EVAP readiness missing
- Likely causes
- LikelyControl wire chafed through and touching ground near the tank or rear wheel arch
- PossibleInternal short inside the leak detection pump
- PossibleWater ingress in the pump connector causing a leakage path to ground
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Often possible to do yourself.Typical cost: €60 – €450
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.