Hello, and welcome. the Code P0700 is a code generated by the PCM, the PCM sets this code, by a detected fault in the trans control module. in short the transmission module will have to scanned for the trans code to know what the actual fault in the transmissin is. here is a description how this code is set.
This diagnostic trouble code (DTC) indicates that a related transmission DTC set in the transmission control module (TCM). The engine control module (ECM) receives the TCM DTC information over the serial data circuit. The ECM turns ON the malfunction indicator lamp (MIL) when the TCM sends a message over the serial data circuit requesting MIL illumination.
The ECM receives a serial data message from the TCM, in order to illuminate the MIL.
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