Upper of both sides not getting cold enough. The defrost heater reads good directly and at the Mother board terminals. Does this mean the defrost thermostat is good also?
Removed evaportator panel and coils were frosted somewhat so I thawed them out w/blowdryer. Compressor kicks off and on. Condenser fan runs, however, I have noticed the evaporator fan does not appear to be working. Will a bad evaporator fan cause my problem of not cooling the upper part of each side? It isn’t running while my compressor and condensor are and I believe it is supposed to. I tried checking the three thermistors and got various values; evaporator therm: 13Kohms, freezer therm: 55kohms, and fresh food therm: 8Kohms (I think because of not being cold enough). So I am leaning toward the evaporator fan.
Any help and advise would be greatly appreciated. Thanks
If I get a good measurement for the heater at the motherboard does this mean the defrost themostat is good also? It is hardwired and I can’t measure it direct without cutting one lead.
I have yet to measure the evaporator fan resistance but I have not seen it run at all. From the schematic it appears it is in parallel with the condensor fan, so it should run at the same time.
The thermistor values I recorded above seem to be realistic from guessing the temperature in the various areas of the freezer and fridge. I don’t think my problem is here then.
Are there any checks I can do at the motherboard to verify the defrost thermostat and evaporator fan without having to measure at the components directly yet?
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If I get a good measurement for the heater at the motherboard does this mean the defrost themostat is good also?[/COLOR]
Yes.
Also it does not sound like you have a defrost problem.
I have yet to measure the evaporator fan resistance but I have not seen it run at all. From the schematic it appears it is in parallel with the condensor fan, so it should run at the same time.
The way I interpret the wiring diagram is only the power to the fans are in parallel. The actual run voltages are separate.
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Are there any checks I can do at the motherboard to verify the defrost thermostat and evaporator fan without having to measure at the components directly yet?[/COLOR]
Yes see the STICKY you should be able to measure the voltages at the control board once you figure out what the pin/plug numbers are.
I found the link "GE Refrigerator Fan Motor Diagnostics" and will do the voltage checks tonight to verify whether the motherboard, fan or both need replaced. I’ll keep you posted on what I find.
Well I got the following measurements at the J2 connector.
Pins 3 to 8 = 13.4 Vdc ; which is good.
Pins 3 to 4 = 0 Vdc ; which is not.
I took off the J2 connector to try and measure the resistance of the motors.
Pins 3 to 8 = 867ohms - condensor fan runs fine
Pins 3 to 4 = 8 ohms - evaporator fan doesn’t come on
Looked at the two resistors under the J2 connector. One reads 2.1 ohms and the other reads 2.5Mohms(basically open) and the resistor body looks like it has been hot, but not burnt.
So is it a possibility that I could replace this 2 ohm resistor and get the motherboard working again or from experience are there usually other board components that are damaged too?
Here is a link from the STICKY that may help http://www.appliance-repair-it.com/refrigerator-fan-motor.html
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So is it a possibility that I could replace this 2 ohm resistor and get the motherboard working again or from experience are there usually other board components that are damaged too?[/COLOR]
Usually overheated resistors mean that the fan is toast as it has been drawing too much current.
Yes often it does mean that other components have been blown especially that now you do not see any voltage at those connections.
Resistors usually blow open and unless very charred do not reduce their resistance.
I cannot comment on what the resistance values should be as I do not know.
It should be color coded or marked.
I can tell you that measuring a resistor with both sides still connected often gives false reading due to other parallel circuits.
If one side of the resistor goes only to the plug then with the plug disconnected you should be getting a true reading.
2.5 meg is not uncommon in an electronic circuit.
Sorry I cannot be of more help but it is probably best that you replace both the fan and the board.
The sticky you provided was what I went off of when I took my initial voltage measurements for the motor circuit outputs. I then measured the evap fan resistance and got 8ohms, so I figured it was shorted since I seen others say it should be around 1.7kohms.
I measured the two resistors and also can see the color codes on them so I know the values. I don’t have an actual schematic for the motherboard, but was just guessing that these may be similar drive circuits and maybe replacing the open 2 ohm resistor might possibly fix the mother board but I can’t say for sure. The fan definitely needs replaced.