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Home >> Infiniti >> 2004 >> Q45 >> Repair and Diagnosis >> Engine Performance >> Engine Control System >> On Board Diagnostic (OBD) System >> Malfunction Indicator Lamp (Mil) >> On Board Diagnostic System Function
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On Board Diagnostic System Function

The on board diagnostic system has the following four functions.

Fig 1: On Board Diagnostic System Function
G00745014Courtesy of NISSAN MOTOR CO., U.S.A.

MIL Flashing Without DTC 

If the ECM is in Diagnostic Test Mode II, MIL may flash when engine is running. In this case, check ECM diagnostic test mode. HOW TO SWITCH DIAGNOSTIC TEST MODE  .

How to switch the diagnostic test (function) modes, and details of the above functions are described later. HOW TO SWITCH DIAGNOSTIC TEST MODE  .

The following emission-related diagnostic information is cleared when the ECM memory is erased.