Theory Of Operation

During the initial ignition on, the Transmission Control Module (TCM) receives the calibrated data from the EEPROM assembly inside the transmission and stores this information in the EEPROM of the TCM. At every ignition on, the TCM compares the stored data in the EEPROM to the transmitted data from the EEPROM in the transmission. If the calibration data does not match the DTC will set and the MIL will illuminate after one failure.