DTC Advanced Diagnostics: P2401, P2402
DTC P2401:Evaporative Emission (EVAP) Leak Check Pump Control Circuit Low Voltage
DTC P2402:Evaporative Emission (EVAP) Leak Check Pump Control Circuit High Voltage

General Description

The evap leak check module vacuum pump is installed in the evap leak check module to create negative pressure in the EVAP passage when performing the evap leak check. The vacuum pump is normally non-energized and inactive. It is only activated when performing the evap leak check. The powertrain control module (PCM) detects a malfunction and stores a DTC when the diagnostic signal of the driver IC of the PCM internal circuit is low continuously for the prescribed time though operation signal is output to the evap leak check module vacuum pump.

Monitor Execution, Sequence, Duration, DTC Type
Execution
Continuous
Sequence
None
Duration
2.0 seconds or more
DTC Type
Two drive cycles, MIL on

Enable Conditions
Condition
Minimum
Maximum
Battery voltage [BATTERY]
10 V
–
[ ]: HDS Parameter

Malfunction Threshold
DTC: P2401

When the diagnostic signal of the driver IC of the PCM internal circuit is low continuously for 2.0 seconds or more while the operation signal is output to the evap leak check module vacuum pump.

DTC: P2402

When the diagnostic signal of the driver IC of the PCM internal circuit is high continuously for 2.0 seconds or more while the operation signal is output to the evap leak check module vacuum pump.

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.

DTC: P2401
EVAP leak check module VMOTOR line short
PCM internal circuit failure

DTC: P2402
EVAP LEAK CHECK MODULE ELCMP line open
EVAP LEAK CHECK MODULE ground line open
EVAP LEAK CHECK MODULE ELCMP line short to power
EVAP LEAK CHECK MODULE ground line short to power
PCM internal circuit failure

Confirmation Procedure
Operating Condition
Turn the vehicle to the ON mode.

With the HDS
Select the EVAP TEST in the INSPECTION MENU, then select the FUNCTION TEST with the HDS.

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 and the freeze data 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, and the freeze data can be cleared with the scan tool Clear command or by disconnecting the 12 volt battery.