Car stalls when in and out of gear

What is your question?

Car was stalling out. Replaced battery because several times the car would be completly dead. isolated the circut by using a circut tester and tested fuses. The tester would show that the batter was in full use when the doors would be open however when the doors closed it would remain the same. When the assist ECU was disconnected it would sometimes show the same thing or would not. Have done the same with the 3 different instrument panel ECU and still having problems. I don't want to replace the ECU control boxes, ETA CS ECU because the testing that I have done has not been consistent to this problem.