P2400: EVAP System Leak Detection Pump Control Circuit/Open

What it means

The control module detects an open or otherwise interrupted control circuit for the EVAP leak detection pump. This can prevent the system from running its leak test.

At a glance

• Usually lights the check-engine light
• Affects emissions; the car can fail an emissions test

How it works

The EVAP leak detection pump helps the control module check the fuel-vapour system for leaks by creating or managing pressure or vacuum. This code sets when the module's control circuit for that pump is open or interrupted, so it may be unable to command the pump and run the test.

Common causes

Most likely first.

1. Open or damaged wiring to the pump
2. Failed leak detection pump
3. Poor connector contact

Symptoms

• Check engine light on

How to diagnose it

1. Record freeze-frame data and check whether the EVAP monitor has completed or failed repeatedly after the code appeared.
2. Locate the leak detection pump using vehicle service information and inspect its connector and harness for disconnection, corrosion, or damage.
3. Check the pump's power and ground connections under the conditions specified by the manufacturer.
4. Test continuity through the pump control wire and check for an open between the pump connector and control module.
5. If the wiring and connections pass, test the pump and its control circuit against the manufacturer's specification.

Common fixes

• Reconnect a loose leak detection pump connector.
• Clean corroded terminals and restore a secure connection.
• Repair an open or damaged section of the pump control wiring.
• Replace the leak detection pump if testing confirms it has failed.

Can I keep driving?

This fault usually does not affect how the vehicle drives, so normal driving is generally possible. The EVAP leak check may not run, which can increase emissions and prevent an emissions inspection from passing.