P2402
Evaporative Emission System Leak Detection Pump Control Circuit High
- Severity
- Low
- Driving
- Drivable — book it in
The circuit the module uses to drive the evaporative emission leak detection pump is reading high, which normally means a short to voltage or a lost earth. On vehicles fitted with one, this pump pressurises the fuel tank and vapour lines so the module can watch for the pressure bleeding away, which is how it detects a leak. With the pump uncontrollable the leak test cannot run, so the vehicle will not complete its emissions readiness checks.
Possible causes
- CommonCorroded or water-damaged connector at the pump
- CommonFailed leak detection pump
- CommonDamaged wiring on the underbody run to the pump
- PossibleBlown fuse or failed relay feeding the pump
- PossibleRodent damage to the harness near the canister
- RareFailed driver inside the control module
What you might notice
- Check engine light on
- Failed emissions test
- Occasionally a smell of fuel
- Usually nothing else - EVAP faults rarely affect how the car drives
What to check, in order
- Inspect the connector and its wiring before condemning the component. Everything in this system lives under the vehicle in the path of road salt and spray, and a corroded connector produces these codes far more often than a failed part does.
- Check the fuse and the pump's power feed before testing the pump itself. A pump that never receives power looks identical to a failed one from the module's side.
- Command the pump on with a scan tool if the vehicle supports it, and listen. A pump that runs when commanded shifts suspicion to the sense circuit rather than the pump.
- Measure the pump winding's resistance against specification. Open or shorted is conclusive; in range means look at the wiring again.
Read this code from your own car
Plug an ELM327 adapter into the OBD-II port under the dashboard. Pin16 reads every stored, pending and permanent code, explains each one like this page does — offline, with no account — and shows what the car recorded when the fault was set.
Where this code sits
P00xxP01xxP02xxP03xxP04xxP05xxP06xxP07xxP08xxP09xxP0AxxP0BxxP0CxxP0DxxP0ExxP0FxxP10xxP11xxP12xxP13xxP14xxP15xxP16xxP17xxP18xxP19xxP1AxxP1BxxP1CxxP1DxxP1ExxP1FxxP20xxP21xxP22xxP23xxP24xxP25xxP26xxP27xxP28xxP29xxP2AxxP2BxxP2CxxP2DxxP2ExxP2FxxP30xxP31xxP32xxP33xxP34xxP35xxP36xxP37xxP38xxP39xxP3AxxP3BxxP3CxxP3DxxP3ExxP3Fxx