P2401 - EVAPORATIVE EMISSION SYSTEM LEAK DETECTION PUMP CONTROL CIRCUIT LOW

The EVAP system (Evaporative Emission Control System) avoids gasoline vapors going out into the atmosphere from the fuel tank or fuel system. This system eliminates fuel vapors because they pollute the atmosphere.

To achieve this, the vent lines from the fuel tank and carburetor bowl direct the vapors to the EVAP storage vessel. The vapors are trapped in the EVAP storage canister until the engine is started. After the vehicle is being driven, the Powertrain Control Module (PCM) opens a bleed valve to allow the vapors to be diverted to the intake manifold storage canister so they can be burned in the engine.

The EVAP system is monitored by the PCM through a pump, which detects possible leaks in the system, which is activated once the engine is turned off. If the DTC P2401 OBD2 code is set, it is because the PCM found that the injection pump circuit of the EVAP system has a low voltage.

• The Check Engine light comes on.
• Emission control system symptoms may be present.

Causes of the P2401 OBDII diagnostic code:

• The gas cap may be faulty.
• Fuel vapor lines may have cracks or leaks.
• The pump wiring harness may have a short.
• The purge control solenoid may be defective.
• The leak detection pump could be in bad condition.

Steps to troubleshoot the P2401 OBD2 fault code:

• Check that the fuel cap is in good condition. Replace it if it does not meet the requirements for the proper system operation.
• Check the EVAP system to make sure that there are no frayed lines. If so, correct these problems.
• Check the leak detection pump wires for damage that would cause a short in the circuit. Replace all the components that are burned, worn, or corroded.
• Replace the detection pump.