1997 Mitsubishi Eclipse ECM voltage regulator problem

Recently this car has been draining the battery to the point it won’t start almost daily, I have replaced the alternator, battery, ignition switch, cables and more. The problem that I have tracked down is the voltage regulator built into the ECM only switches to charging the battery when you rev the engine until about the point the turbo kicks in then it starts recharging the battery, if you don't rev it it won't start charging. A 12 volt battery at 12.3 volts to starts drops to about 5 volts at startup and then if you don’t rev the engine the battery won’t charge and then when the voltage drops to about 10.7 volts it starts running crappy, soon after that it won’t have enough power to start the car. Also it will throw a check engine light and OBD2 code of (P1500 Generator FR Terminal Circuit Malfunction). I have read other forums and I am pretty sure the problem is in the ECM and the pin is number 41 no trace of damage on the circuit board, but I can hear some component clicking in and out when the car is driving and the battery voltage is dropping and the engine starts running bad, my question is does anyone know what component on the board is the voltage regulator or switch that kicks it in and out. I would like to make a board repair rather than buying a ECM any help?