Precautions In Diagnosing Trouble

Precautions in Diagnosing Trouble

^ Don't disconnect couplers from TCM, battery cable from battery, TCM ground wire harness from engine or main fuse before checking the diagnosis information (DTC, freeze frame data, etc.) stored in TCM memory. Such disconnection will clear memorized information in TCM memory.
^ 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.
^ Be sure to read Precautions for Electrical Circuit Service before inspection and observe what is written there.
^ TCM replacement
^ When substituting a known-good TCM, check that all relays and actuators have resistance of specified value. Neglecting this check may result in damage to good TCM.
^ Communication of ECM, BCM, combination meter, keyless start control module (if equipped), ABS / ESP control module, 4WD control module (if equipped), steering angle sensor (ESP model), Yaw rate G sensor (ESP model), TCM and DLC, is established by CAN (Controller Area Network). Therefore, handle CAN communication line with care.