DTC P2401

DTC P2401	EVAP system leak detection pump motor circuit low input
DETECTION CONDITION	The PCM monitors pump load current (EVAP line pressure), while evaporative leak monitor is operating. If the pump load current is lower than specified, the PCM determines the EVAP system leak detection pump motor circuit has a malfunction. Diagnostic support note This is a intermittent monitor (CCM). The MIL illuminates if the PCM detects the above malfunction condition in two consecutive drive cycles or in one drive cycle while the DTC for the same malfunction has been stored in the PCM. PENDING CODE is available if the PCM detects the above malfunction condition during the first drive cycle. FREEZE FRAME DATA (Mode 2/Mode 12) is available. The DTC is stored in the PCM memory.
POSSIBLE CAUSE	EVAP system leak detection pump connector or terminals malfunction Open circuit or short to ground in EVAP system leak detection pump power supply circuit Short to ground in wiring harness between main relay and EVAP system leak detection pump terminal A EVAP system leak detection pump power supply circuit related fuse malfunction Open circuit in wiring harness between main relay and EVAP system leak detection pump terminal A Short to ground in wiring harness between EVAP system leak detection pump terminal D and PCM terminal 1U PCM connector or terminals malfunction EVAP system leak detection pump motor circuit and ground circuit are shorted to each other Open circuit in wiring harness between EVAP system leak detection pump terminal D and PCM terminal 1U EVAP system leak detection pump malfunction PCM malfunction

DIAGNOSTIC PROCEDURE

STEP	INSPECTION		ACTION
1	VERIFY FREEZE FRAME DATA (MODE 12) HAS BEEN RECORDED Has the FREEZE FRAME DATA (Mode 12) been recorded?	Yes	Go to the next step.
1		No	Record the FREEZE FRAME DATA (Mode 12) on the repair order, then go to the next step.
2	VERIFY RELATED SERVICE BULLETINS AVAILABILITY Verify related Service Bulletins availability. Is any related Service Bulletins available?	Yes	Perform the repair or diagnosis according to the available Service Bulletins. If the vehicle is not repaired, go to the next step.
2		No	Go to the next step.
3	VERIFY RELATED PENDING CODE AND STORED DTC Turn the ignition switch off, then to the ON position (Engine off). Verify related PENDING CODE and stored DTC. Is the DTC P2405 also present?	Yes	Go to the applicable DTC inspection. (See DTC P2405 ).
3		No	Go to the next step.
4	INSPECT EVAP SYSTEM LEAK DETECTION PUMP CONNECTOR AND TERMINALS Turn the ignition switch off. Disconnect EVAP system leak detection pump connector. Inspect for poor connection (such as damaged/pulled-out pins, and corrosion). Is there any malfunction?	Yes	Repair or replace the connector or terminals, then go to Step 11.
4		No	Go to the next step.
5	INSPECT EVAP SYSTEM LEAK DETECTION PUMP POWER SUPPLY CIRCUIT FOR OPEN CIRCUIT OR SHORT TO GROUND EVAP system leak detection pump connector is disconnected. Turn the ignition switch to the ON positron (Engine off) Measure the voltage between EVAP system teak detection pump terminal A (wiring harness-side) and body ground. Is the voltage B+ ?	Yes	Go to the next step.
5		No	Inspect the EVAP system leak detection pump power supply circuit related fuse. If the fuse is melt Repair or replace the wiring harness for a possible short to ground. Replace the fuse. If the fuse is deterioration: Replace the fuse. If the fuse is normal: Repair or replace the wiring harness for a possible open circuit. Go to Step 11.
6	INSPECT EVAP SYSTEM LEAK DETECTION PUMP MOTOR CIRCUIT FOR SHORT TO GROUND EVAP system leak detection pump connector is disconnected. Turn the ignition switch off. Inspect for continuity between EVAP system leak detection pump terminal D (wiring harness-side) and body ground. Is there continuity?	Yes	If the short to ground circuit could be detected: Repair or replace the wiring harness for a possible short to ground. If the short to ground circuit could not be detected: Replace the PCM (short to ground in PCM internal circuit). (See PCM REMOVAL/INSTALLATION ). Go to Step 11.
6		No	Go to the next step.
7	INSPECT PCM CONNECTOR AND TERMINALS Disconnect the PCM connector. Inspect for poor connection (such as damaged/pulled-out pins, and corrosion). Is there any malfunction?	Yes	Repair or replace the connector or terminals, then go to Step 11.
7		No	Go to the next step.
8	INSPECT EVAP SYSTEM LEAK DETECTION PUMP MOTOR CIRCUIT AND GROUND CIRCUIT FOR SHORT TO EACH OTHER EVAP system leak detection pump and PCM connectors are disconnected. Inspect for continuity between EVAP system leak detection pump terminals D and B (wiring harness-side). Is there continuity?	Yes	Repair or replace the wiring harness for a possible short to each other, then go to Step 11.
8		No	Go to the next step.
9	INSPECT EVAP SYSTEM LEAK DETECTION PUMP MOTOR CIRCUIT FOR OPEN CIRCUIT EVAP system leak detection pump and PCM connectors are disconnected. Inspect for continuity between EVAP system leak detection pump terminal D (wiring harness-side) and PCM terminal 1U (wiring harness-side). Is there continuity?	Yes	Go to the next step.
9		No	Repair or replace the wiring harness for a possible open circuit, then go to Step 11.
10	INSPECT EVAP SYSTEM LEAK DETECTION PUMP Inspect the EVAP system leak detection pump. (See EVAPORATIVE EMISSION (EVAP) SYSTEM LEAK DETECTION PUMP INSPECTION ). Is there any malfunction?	Yes	Replace the EVAP system leak detection pump, then go to the next step. (See EVAPORATIVE EMISSION (EVAP) SYSTEM LEAK DETECTION PUMP REMOVAL/INSTALLATION ).
10		No	Go to the next step.
11	VERIFY TROUBLESHOOTING OF DTC P2401 COMPLETED Make sure to reconnect all disconnected connectors. Clear the DTC from the PCM memory using the M-MDS. Perform the KOEO self test. (See KOEO/KOER SELF TEST ). Is the same DTC present?	Yes	Replace the PCM, then go to the next step. (See PCM REMOVAL/INSTALLATION ).
11		No	Go to the next step.
12	VERIFY AFTER REPAIR PROCEDURE Perform the "AFTER REPAIR PROCEDURE". (See AFTER REPAIR PROCEDURE ). Are any DTCs present?	Yes	Go to the applicable DTC inspection. (See DTC TABLE ).
12		No	DTC troubleshooting completed.