Electronic Control System: Self-diagnosis

The PCM detects a failure of a signal a sensor or another control unit and stores a Temporary DTC or a DTC.

Depending on the failure, a DTC is stored in either the first or the second drive cycle (DTC P0457 turn on the malfunction indicator lamp (MIL) during the third drive cycle). When a DTC is stored, the PCM turns on the MIL by a signal sent to the gauge control module, via F-CAN.

• One Drive Cycle Detection Method 

  When an abnormality occurs in the signal from a sensor or from another control unit, the PCM stores a DTC for the failure and turns on the MIL immediately.

• Two Drive Cycle Detection Method 

  When an abnormality occurs in the signal from a sensor or from another control unit in the first drive cycle, the PCM stores a Temporary DTC. If the failure continues in the second drive cycle, the PCM stores a DTC and turns on the MIL.