Precautions in Diagnosing Trouble
Do not disconnect couplers from TCM, battery cable from battery, TCM ground wire harness from engine or main fuse before checking the diagnostic information (DTC, freeze frame data, etc.) stored in TCM memory.
Such disconnection will clear memorized information in TCM memory.
For M13 engine model with VVT, diagnostic information stored in TCM memory can be cleared as well as checked by using SUZUKI scan tool or generic scan tool. Before using scan tool, read its Operator’s (Instruction) Manual carefully to have good understanding as to what functions are available and how to use it.
It is indistinguishable which module turns on MIL because not only ECM but also TCM turns on MIL. Therefore, check both ECM and TCM for DTC when MIL lights on.
When checking TCM for DTC, keep in mind that DTC is displayed on the scan tool as follows depending on the scan tool used.
SUZUKI scan tool displays DTC detected by TCM.
Generic scan tool displays DTC detected by each of ECM and TCM simultaneously.
For M13 engine model without VVT, using SUZUKI scan tool the diagnostic information stored in TCM memory can be checked and cleared as well. Before its use, be sure to read Operator’s Manual supplied with it carefully to have good understanding of its functions and usage.
Not using scan tool, the DTC stored in TCM memory also can be checked and cleared. DTC stored in the TCM memory is outputted by flashing of transmission warning light with diagnosis terminal of monitor connector grounded. If no DTC is stored in TCM memory, DTC No.12 is outputted repeatedly. If one or more DTCs are stored in TCM memory, they are outputted starting from smallest code number in increasing order.
After all DTCs are outputted, all DTCs are outputted repeatedly.
When replacing TCM with used one, all learned controls which are stored in TCM memory should be initialized after the replacement referring to Learning Control Memory Initialization Inspection . Neglecting this initialization may cause excessive shift shock.
Be sure to read Precautions for Electrical Circuit Service before inspection and observe what is written there.
TCM and/or ECM replacement
When substituting a known-good TCM and/or ECM, check that all relays and actuators have resistance of specified value.
Neglecting this check may result in damage to good TCM and/or ECM.
For M13 engine model with VVT, communication of ECUs, ECM and TCM, is established by CAN (Computer Area Network). Therefore, handle CAN communication line with care.