Engine Diagnosis General Description
The engine and emission control system in this vehicle are controlled by ECM. ECM has an On-Board Diagnostic system which detects a malfunction in this system and abnormality of those parts that influence the engine exhaust emission. When diagnosing engine troubles, be sure to have full understanding of the outline of On-Board Diagnostic System Description:K9K and each item in Precautions in Diagnosing Trouble:K9K and execute diagnosis according to Engine and Emission Control System Check:K9K .
There is a close relationship between the engine mechanical, engine cooling system, exhaust system, etc. and the engine and emission control system in their structure and operation. In case of an engine trouble, even when the warning light (MIL, injection warning light, and/or red stop warning light) doesn’t turn ON, it should be diagnosed according to this flow table.