•  Shift solenoid A, B is installed on the front valve body. The solenoids turn ON and OFF in response to signals output from the TCM. According to the ON or OFF status of shift solenoid A or shift solenoid B, the 1st gear engine brake operates or the gear shifts into change. As a fail-safe function, if any shift solenoid abnormality occurs, the TCM will disable the current to the solenoids.