LG Refrigerator 4 wire DC Fan test(Pwm fans) How to test with 9 volt battery. Appliance Repair.

This is how you can test if the 4 wire DC.( Pwm)
Fans are good. These are Evaporator fans in a LG refrigerator.
My Customer had bought one off Amazon
Part # Eau65058313( lot# 24058)
And when I ordered got the same lot number
Both failed this test.. This is the smaller round motor on left side.
The bigger Motor is part number EAU65058313
The new motor worked.. ( check parts diagram for your model.
I had searched for how to test run these and found a few videos but they were not speaking English.
You can use a 12 volt power supply.. or the 9 volt battery worked fine for me.
Red and yellow wires go to positive (+)
The yellow is your pulse signal.
Black to negative (-)
You may have to spin the motor to get it going.
It's always best to test the motor.. before you install..
You may have a bad Control board or connection in block or bad wire if your fans won't run installed
A bad Door switch can also be a issue.
You will have to find a service manual for your model to test voltages at Control board.
Often there is 10 to 20 sec delays after door switch is made before fan.. power output is turned on...
GE delays as well..
Hope this helps if you're a professional or DIYer.