P2401EVAP System

Evaporative Emission System Leak Detection Pump Control Circuit Low

The powertrain control module has detected that the voltage in the leak detection pump control circuit is lower than expected. The leak detection pump pressurizes the EVAP system to check for fuel vapor leaks. A low voltage reading usually points to a short to ground, a failed pump, or a wiring problem.

🚗 Yes, you can drive safely. This is an emissions fault that does not affect engine performance or safety, but the code should be repaired to pass emissions testing.

LOW

severity

🎯 Top Causes, Ranked by Likelihood

#1Faulty leak detection pump$120-$300

40%

The internal pump motor or solenoid has failed, drawing the control circuit voltage low.

#2Short to ground in control wiring$80-$250

25%

A chafed or pinched wire near the pump is shorting the control circuit to ground.

#3Corroded or loose connector$40-$150

20%

Moisture and corrosion at the pump connector cause a low or intermittent signal.

#4Failed PCM driver$200-$600

15%

The control module output driver for the pump has failed internally.

🩺 Common Symptoms

Check engine light is on
No noticeable drivability change
Possible faint fuel odor near the tank
Failed or pending emissions readiness monitor

💰 Repair Cost: DIY vs Shop

DIY Cost

$120-$300

Shop Cost

$200-$450

📋 Free OBD2 Code Cheat Sheet

The 50 most common codes with likely cause and DIY fix cost. Sent once, no spam.

🔧 How to Diagnose P2401

1Inspect the leak detection pump connector and wiring for damage, corrosion, or looseness.

2Measure the control circuit voltage and resistance against the service manual specification.

3Test the pump motor resistance and compare it to spec; replace the pump if out of range.

4Clear the code and run an EVAP monitor drive cycle to confirm the repair.

❓ Frequently Asked Questions

Is P2401 safe to drive with?

Yes. It is an emissions code that does not affect how the vehicle runs. Repair it before your next emissions test.

What is a leak detection pump?

It is a small pump that pressurizes the EVAP system so the computer can detect fuel vapor leaks that would otherwise release emissions.

Will this code cause a fuel smell?

It can if the underlying issue involves a leak, but often the code is purely electrical with no odor present.

🔗 Related Codes

P2402P2404P2405P0455P0442