How to test a fridge parts, fridge isn't cooling?

Question

I have a fridge (bottom freezer) that has stopped cooling. The light is still on, the digital controls are out, and there's no cooling on the top or bottom.

I'm told it is likely one of a few things:

# The compressor

# The Thermostat

# The overload, relay, or capacitor

# The defrost timer

# The condenser fan motor

How do I test these things? I have a multimeter, lots of tools, and I've done a lot of work on other appliances, but not fridges.

Answer 1

Try this link. Sounds like you are comfortable using tools and have my philosophy: "Hey, what the heck, it's already broke!"

http://home.howstuffworks.com/how-to-rep...

Answer 2

If the LCD digital control board is not reading anything,it's the board or the sensors.

It's not calling for the compressor to run.Check by checking for voltage at the compressor terminals,C to R.If it's calling, there will be line voltage at these terminals and the compressor will most likely be hot.If it's not calling.there won't be any voltage at the these terminals and the compressor will be cold.

Check that first,then post another question.

Answer 3

You have a board out if your digital control is blank AND it is not cooling. (with some failures and brands you can have a blank control but it still works).

If you have a digital control you do not even have a thermostat, it is electronic using thermistors.

Way too little information.  You didn't even give the brand. i.e. GE has two boards and for them the one you see is only a temperature control board, the motherboard is in the back. With whirlpool and frigidaire they have a single board as do some Amanas. Some Amana and Maytags had a separate power board.  

If the control is blank likely either the board is fried or you lost the transformer that powers it. It is possible the power isn't getting there for some reason but that is not as likely.

First you need to find the tech sheet they tuck in the units. Can't tell you where because different brands put them in different places and the location can very with model and age too.

If you can bring up your model number someplace like SearPartsDirect sometimes it shows the location of the tech sheet, likely on the cabinet picture or maybe with the control.

Without specialized equipment and/or a very good knowledge of the particular unit you can not really "diagnose" boards. Mainly you check power in and power out of them. If it is wrong it is bad.

I will smell them first. A burnt board or component on a board is not hard to detect. You can pull them and visually inspect them for burnt components as well. It is a little easier in your case if it is just dead as opposed to some function not working. In the latter case it can be that a separate component shorted out and took out the board. When that happens you risk losing a new board if the bad component is not replaced also.

But as I said, that is less likely in your case with it out totally. If everything is on a single board, I would verify it has power to it and replace the board.

As a tech I kept used rebuilt boards for testing. That was the simplest way. Replace it to test. No real need to diagnose further.

With electronics problems as seems your case it is really beyond the ability of most to do it easily. Even most techs don't understand the electronics well, but don't really need to. We replace parts until it works. lol.

Since boards, once installed, can't be returned you run the risk of buying unneeded parts that eventually cost you more than a repair call. Or you risk blowing a new board. This is more like computer work than technical or mechanical work.   (they are computer boards!)  

    

Good Luck.