Description of On-Board Diagnostics

On-Board Diagnostic System Description





For automatic transaxle control system, TCM has following functions.
^ When TCM detects a malfunction in A/T control system, it stores malfunction DTC and at the same time transmits DTC of that malfunction to ECM. (Based on this signal, ECM turns ON Malfunction Indicator Lamp (MIL) (1) and stores DTC / freeze frame data in its memory.)
^ If no malfunction is detected after detecting malfunction, TCM immediately halts to transmit DTC of that malfunction to ECM, however, DTC stored in TCM memory will remain. If ECM receives no DTC of malfunction for 3 driving cycles continuously, it turns MIL off although DTC stored in ECM memory will also remain.
^ It is possible to communicate with ECM and/or TCM through Data Link Connector (DLC) (2) by using SUZUKI scan tool (3). (Diagnostic information can be checked and erased by using scan tool.)
^ It is also possible to check DTC stored in TCM memory by displaying DTC on digital display odometer (5). DTC is displayed on odometer by connecting diagnosis switch terminal (7) with ground terminal (8) of monitor connector (color in Blue) (6), with reset button (4) pressed. If no malfunction DTC is stored in TCM memory, DTC No.12 is displayed. If one or more DTCs are stored in TCM memory, they are displayed 3 seconds each sequentially. After all DTCs are displayed, they are displayed in the same manner again.

2 Driving Cycle Detection Logic
When a malfunction is detected during initial driving cycle, TCM transmits a data to inform ECM of malfunction occurrence. At this time, ECM stores a corresponding pending DTC in its memory. (but MIL does not light). If the same malfunction is also detected in next driving cycle, ECM lights MIL when it receives a data informing occurrence of a malfunction from TCM.

Freeze Frame Data
Refer to On-Board Diagnostic System Description.