P2400EVAP System Leak Detection Pump Control Circuit/Open
- 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
- P2400 is stored when the engine computer finds the drive line of the evaporative leak detection pump open, so the pump cannot be switched for the tank leak test. GM's tables for the sealed fuel system of the Volt (2011, 2016) compare the commanded and actual driver state and treat a low voltage in the off state, equal to more than 200 kOhm to ground, as an open; 20 failed samples out of 25 at 250 ms each set a Type B code. VW's 2014 Golf data book flags a signal voltage of roughly 4.4-5.6 V. Toyota names P2400 with failure types 7E/7F on A25A engines, and VW traced P2400 on the 2011-2014 Touareg 3.6 to coolant entering the pump's vacuum line. P2401 and P2402 are the short-circuit siblings. The leak test cannot run; the car drives normally.
- What you may notice
- Check engine light
- EVAP readiness monitor stays incomplete
- No noticeable change in driving behaviour
- Likely causes
- LikelyCorroded or loose pump connector, broken wire in the drive line
- PossibleOpen winding or internal fault in the leak detection pump
- RareCoolant in the pump's vacuum supply line from a failed coolant pump changeover valve (VW Touareg 3.6)
- RareFaulty output stage in the engine control module
- 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.