Engine Diagnosis General Description

The engine and emission control system in this vehicle are controlled by ECM. ECM has an OBD system which detects a malfunction in this system and abnormality of those parts that influence the engine exhaust emission. When diagnosing engine troubles, have full understanding of the outline of OBD System Description:D16AA and each item in “Precautions for Diagnosing Trouble” under Precautions for Engine (D16AA) and execute diagnosis according to Engine and Emission Control System Check:D16AA.

There is a close relationship between the emission system, engine mechanical, engine cooling system, ignition system, exhaust system, etc. in their structure and operation. In case of an engine trouble, even when the MIL does not turn on, it should be diagnosed according to Engine and Emission Control System Check:D16AA.