DTC Advanced Diagnostics: P2400 (3.0L Engine)

DTC P2400: Evaporative Emission (EVAP) Leak Check Pump Control Circuit Open

General Description

Courtesy of HONDA, U.S.A., INC.

The evaporative emission (EVAP) leak check module vacuum pump absorbs the air in the fuel tank and the EVAP leak check module pressure sensor measures the vacuumed pressure. The powertrain control module (PCM) compares the vacuumed pressure with a reference pressure to detect leaks of the fuel tank. The PCM controls the ON/OFF of the EVAP leak check module vacuum pump. If the VMOTOR terminal voltage level is in intermediate voltage while the PCM outputs OFF signal to the EVAP leak check module vacuum pump or if the EVAP leak check module vacuum pump control circuit detects an over current, the PCM detects a malfunction and stores a DTC.

Monitor Execution, Sequence, Duration, DTC Type

Execution	Continuous
Sequence	None
Duration	0.5 second or more
DTC Type	Two drive cycles, MIL on

Enable Conditions

Condition	Minimum	Maximum
12 volt battery voltage [Battery]	10.0 V	-

[ ]: HDS Parameter

Malfunction Threshold

Either of the condition occurs:

The VMOTOR terminal voltage level is in intermediate voltage for at least 0.5 second while the PCM outputs OFF signal to the EVAP leak check module vacuum pump.
The EVAP leak check module vacuum pump control circuit detects an over current for at least 0.5 second.

Possible Cause

NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.

EVAP leak check module vacuum pump VMOTOR line open
EVAP leak check module vacuum pump power supply line open
EVAP leak check module vacuum pump failure

Diagnosis Details

Conditions for setting the DTC

When a malfunction is detected during the first drive cycle, a Pending DTC is stored in the PCM memory. If the malfunction returns in the next (second) drive cycle, the MIL comes on and a Confirmed DTC, the freeze data, and the on-board snapshot are stored.

Conditions for clearing the DTC

The MIL is cleared if the malfunction does not return in three consecutive trips in which the diagnostic runs. The MIL, the Pending DTC, the Confirmed DTC, the freeze data, and the on-board snapshot can be cleared with the scan tool clear command.