g.e. refrigerator

Hello

I am an appliance tech. Normally I don’t have any trouble with repairs and completeing the job in a timely manner with good results. Everything would be fine if there wasn’t such a critter as GE refrigerators. I have many times replaced the control board, the defrost limit and the defrost heater. They still won’t defrost. This is taking into account on bottom freezers and terminator models you are supposed to clip number 2 wire on the 9 pin connector. It is supposed to be a white wire. Sometimes it is white and sometimes white with a yellow stripe. Every tech I know has the same problem. Is there any way to find what the problem. I have too many recalls on these.

Thank you

Certified10

I have seen units that had a bad evaporator thermistor, caused an incomplete defrost and if too high a resistance, the fridg will never go in defrost.You can check these right at the motherboard, just go to the GE fridg sticky above for pin #s and thermistor resistance chart.
I always use the manual test if unsure what problem exists.
While the fridg is running and the freezer cold, pull the 3 pin power connector off the motherboard after you unplug the unit. Put a wire jumper between the plug mating pins for the motherboard labeled pins def. and line.
If it now defrosts, you have a bad motherboard, if not, bad termination thermostat or heater.