P2401

DTC P2401 EVAPORATIVE EMISSION SYSTEM LEAK DETECTION PUMP CONTROL CIRCUIT LOW


GENERAL DESCRIPTION
The DM-TL (Diagnostic Module Tank Leakage) is used to monitor the evaporative system for leaks. The diagnostic module consists of an air filter, an electrical driven air pump, a change-over valve and a 0.02 inch orifice for reference measurement. Heated type Module applied to improved Leakage Detection Module. Using the heated DM-TL can completely eliminate the humidity influence. So, the Leakage detection is never stopped caused by the current fluctuation (due to dew effects at extreme high humidity).

DTC DESCRIPTION
PCM sets DTC P2401 if the PCM detects that the DM-TL Pump motor control line is open or short to ground.

DTC Detecting Condition:

Specification:

Schematic Diagram:

MONITOR DTC STATUS
This is the inspection procedure to determine whether it is present DTC or memoried one by monitoring the current signal or by using the function of oscilloscope with Hi-scan pro.
1. Connect scantool to Data Link Connector(DLC).
2. Warm up the engine to normal operating temperature.





3. Evap. Leakage Test
Evaporative Emissions Systems (EVAP) Leak Tests can be run by the Scan Tool. The tests are automated and provide either a pass-fail result or directions to check for DTCs.
1. Connect scantool to Data Link Connector(DLC).
2. Warm up the engine to normal operating temperature.
3. Perform "07 EVAP. LEAKAGE TEST" mode
4. Is DTC P2401 set again?

YES: Go to "W/Harness Inspection" procedure.

NO: Fault is intermittent caused by poor contact in the sensor's and/or PCM's connector or was repaired and PCM memory was not cleared. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and go to "Verification vehicle Repair" procedure

TERMINAL & CONNECTOR INSPECTION
1. Many malfunctions in the electrical system are caused by poor harness and terminals. Faults can also be caused by interference from other electrical systems, and mechanical or chemical damage.
2. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage.
3. Has a problem been found?

YES: Repair as necessary and go to "Verification of vehicle Repair" procedure.

NO: Go to "Control circuit inspection" procedure.

CONTROL CIRCUIT INSPECTION
1. Check for short to ground in harness
1. Ignition "OFF"
2. Disconnect DM-TL connector and PCM connector
3. Ignition "ON" & Engine "OFF"




4. Measure resistance between terminal 1 of DM-TL harness connector and chassis ground..
Specification: infinite

5. Is measure resistance within Specification?

YES: Go to "Check for short between Pump Control and Solenoid Control harness as below.

NO:
- Short circuit to chassis ground between DM-TL harness connector and PCM harness connector.
- Repair as necessary and then go to "Verification of Vehicle Repair" procedure.

2. Check for short between Pump Control and Solenoid Control harness
1. Ignition "OFF".
2. Disconnect DM-TL connector and PCM connector.
3. Ignition "ON" & Engine "OFF"




4. Measure resistance between terminal 1 and 2 of DM-TL harness connector.
Specification: infinite

5. Is measure resistance within Specification?

YES: Go to "Component Inspection" procedure.

NO:
- Shorted circuit between Pump Control circuit and Solenoid Control circuit.
- Repair as necessary and then go to "Verification of Vehicle Repair" procedure.

COMPONENT INSPECTION

1. Check for short between Pump Control and chassis ground.
1. Ignition "OFF
2. Disconnect DM-TL connector.




3. Measure resistance between terminal 1 of DM-TL harness connector and chassis ground.(To DM-TL side)
Specification: infinite

4. Is measure resistance within Specification?

YES: Substitute with a known-good PCM and check for proper operation. If the problem is corrected, replace PCM and then go to Verification of Vehicle Repair" procedure.

NO: Substitute with a known-good Pump motor and check for proper operation. If the problem is corrected, replace Pump motor and then go to "Verification of Vehicle Repair" procedure.

VERIFICATION OF VEHICLE REPAIR
After a repair, it is essential to verify that the fault has been corrected.
1. Monitor and record the Freeze Frame Data for the Diagnostic Trouble Code (DTC) which has been diagnosed.
2. Using a Scantool, Clear the DTCs.
3. Operate the vehicle within conditions noted in the freeze frame data or enable condition.
4. Monitor that all rediness test have been verified as "Complete"
5. Are any DTCs present?

YES: Go to the applicable troubleshooting procedure.

NO: System is performing to specification at this time.