On-Board Diagnostic System Description

For automatic transmission control system, PCM has the following functions.

Refer to INSPECTION OF ECM (PCM) AND ITS CIRCUITS .

• When the ignition switch is turned ON with the engine at a stop, malfunction indicator lamp (MIL) turn ON to check the bulb of the MIL.
• When PCM detects a malfunction in A/T control system (and/or a malfunction which gives an adverse effect to vehicle emission) while the engine is running, it makes the malfunction indicator lamp in the meter cluster of the instrument panel turn ON and stores the malfunction area (DTC according to SAE J2012) in its memory.
• (If it detects that continuously 3 driving cycles are normal after detecting a malfunction, however, it makes MIL turn OFF although DTC stored in its memory will remain.)
• It is possible to communicate through DLC by using not only SUZUKI scan tool but also OBD-II generic scan tool which are in compliance with SAEJ1978. (Diagnostic information can be accessed by using a scan tool.)

Fig 1: Identifying Malfunction Indicator Lamp, Scan Tool And DLC

Courtesy of SUZUKI OF AMERICA CORP.