Emissions - MIL ON, False DTC P0456 EVAP Leak
XT303-09X-TYPE
DATE 12/02
MODEL
2002-03 MY
X-TYPE
VIN
C00001-D14654
False Flagging Of DTC P0456 - No Evaporative Leak Present - Repair Procedure
Issue:
This Technical Bulletin provides information to aid in the diagnosis of the Malfunction Indicator Lamp (MIL) illuminating and DTC P0456 flagging without a leak being present. It has been determined that DTC P0456 may be false flagging when there is no actual leak present.
Engineering will provide a definitive fix as soon as possible. As a temporary solution, if no leak is present, the ECM should be re-calibrated as an existing module using the calibration on WDS disc issue 21. This will reduce the possibility of the problem occurring.
Note:
Changing fuel tanks or any other Evaporative (EVAP) related components would not prevent a falsely flagged DTC P0456 recurring. Components should only be changed if the root cause of a leak can be identified.
Action:
Determine the likelihood of the presence of a leak in the fuel tank, using one of the following methods:
^ If GDS 500/510 is not available: Carry out EVAP system pressure test using K-line smoke machine or VacuTec or equivalent .020 gross leak detection equipment.
^ If a GDS 500/510 is available, interrogate Test Identities (TID) 6 (see procedure below). If the value of this TID is greater than or equal to 710 a leak is likely. Further investigation to establish the root cause of the leak should be carried out, using the K-line equipment.
Note:
^ TID 6 must be checked before clearing DTCs.
^ TID 6 cannot be interrogated using WDS.
^ The procedure for checking TID 6 is only to be used as a temporary measure; it should not be used when the definitive fix is available.
1. Connect GDS 500/510 to the data link connector.
2. At main menu, highlight 'EOBD/OBDII scan tool' and press check mark.
3. Navigate to 'select option' menu.
4. At 'select option' menu, highlight 'On-Board Monitoring Test Results' and press check mark.
5. Highlight 'Non-continuous' and press check mark.
6. Highlight 'TID OO (11)' and press check mark.
7. Highlight 'T06' (1)' and press check mark.
8. TID value is now displayed (Illustration 1).
If no leak is present in the fuel tank, recalibrate the ECM as an existing module using the calibration on WDS disc issue 21. This will reduce the possibility of the problem occurring.