Abstract: An analyzing and fault indicating system for automatic transmissions and their related electro-mechanical operating functions, including vacuum pressure and/or fluid pressure and/or governor and/or computer controlled electrical circuits on automotive vehicles so equipped. This system inserts a passive electron flow measuring ampere meter in series with, and continuously monitors the transmission's principal solenoid winding, called a torque converter clutch (T.C.C.) solenoid, for manufacturers specified quantity of electron flow for satisfactory solenoid operation. Contained in an apparatus case are the system's lamps, light emitting diodes and an ammeter which functions to indicate faults or satisfactory operation of the automatic transmission and/or related function controls. The apparatus case is mechanically suspended from the in-vehicle rear view mirror or its immediate vicinity and connected by two cables to the automatic transmission.