P2401 Fault Code

Evaporative Emission System Leak Detection Pump Control Circuit Low

• What does that mean?
• Symptoms
• Causes
• Solutions

The P2401 fault code indicates an issue with the Evaporative Emission System Leak Detection Pump Control Circuit, which typically signals that the control circuit for the leak detection pump is operating at a lower voltage than expected. This circuit helps in detecting leaks in the evaporative emission system, which is crucial for keeping harmful vapors from escaping into the atmosphere.

• The evaporative emission system is responsible for capturing and storing fuel vapors from the fuel tank.
• A leak detection pump is a vital component that helps monitor and identify any leaks in this system.
• A low voltage in the control circuit may prevent the pump from functioning effectively, leading to potential increased emissions and failing vehicle emissions tests.

What are the symptoms of the P2401 code?

When the P2401 code is triggered, you might notice the following symptoms:

• Illuminated check engine light on the dashboard
• Possible decrease in fuel efficiency due to the malfunctioning emission system
• Engine may run rough or have difficulty starting
• Failure during emissions testing, which may prevent the car from passing state inspections
• Fuel odor due to escaping vapors if there is a significant leak.

What causes the P2401 code?

Several factors can contribute to the P2401 fault code, including:

• Damaged or worn wiring in the leak detection pump circuit
• Faulty leak detection pump that fails to operate correctly
• Corroded connectors or terminals leading to poor electrical connection
• Issues with the vehicle's Engine Control Module (ECM) that fails to supply adequate voltage to the system
• Faulty vacuum lines or seals that may be affecting the functionality of the evaporative emission system.

How to fix P2401?

To resolve the issues associated with the P2401 code, consider the following steps:

• Conduct a thorough inspection of the wiring and connectors related to the leak detection pump circuit for any signs of damage or corrosion.
• Test the leak detection pump for functionality and replace it if necessary.
• Ensure all vacuum lines and seals in the evaporative emission system are intact and functioning properly.
• Clear the fault codes after repairs and conduct a drive cycle to check if the code reappears.
• If the issues persist, further diagnostics may be needed to check the ECM or other components related to the emission system.