Permanent Diagnostic Trouble Code (Permanent DTC)

DIAGNOSIS SYSTEM (ECM)

DIAGNOSIS DESCRIPTION : Permanent Diagnostic Trouble Code (Permanent DTC)

Permanent DTC is defined in SAE J1979/ISO 15031-5 Service $0A.
ECM stores a DTC issuing a command of turning on MIL as a permanent DTC and keeps storing the DTC as a permanent DTC until ECM judges that there is no presence of malfunction.
Permanent DTCs cannot be erased by using the erase function of CONSULT or Generic Scan Tool (GST) and by disconnecting the battery to shut off power to ECM. This prevents a vehicle from passing the in-use inspection without repairing a malfunctioning part.
When not passing the in-use inspection due to more than one permanent DTC, permanent DTCs should be erased, referring to this manual.
NOTE:
- The important items in in-use inspection are that MIL is not ON, SRT test items are set, and permanent
DTCs are not included.
- Permanent DTCs do not apply for regions that permanent DTCs are not regulated by law.

PERMANENT DTC SET TIMING

The setting timing of permanent DTC is stored in ECM with the lighting of MIL when a DTC is confirmed.