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:
PERMANENT DTC SET TIMING
The setting timing of permanent DTC is stored in ECM with the lighting of MIL when a DTC is confirmed.
Diagnosis description : system readiness
test (SRT) code
Diagnosis description : malfunction indicator lamp (MIL)Wiring diagram
Headlamp
Wiring diagram
Daytime light system
Wiring diagram
Auto light system
Wiring diagram
Front fog lamp
Wiring diagram
Turn signal and hazard warning lamps
Wiring diagram
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Preparation
Special Service Tools
The actual shape of the tools may differ from those illustrated here.
Commercial Service Tools
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Ecu diagnosis information
Abs actuator and electric unit
(control unit)
Reference Value
VALUES ON THE DIAGNOSIS TOOL
CAUTION:
The display shows the control unit calculation data, so a
normal value might be displayed even in the
event the output circuit (harness) is open or short-circuited.
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