The start relay may be malfunctioning if your refrigerator stops making cold air.The compressor in the fridge starts making cold air when the relay starts.If you need to replace the relay, you can easily check it.Make sure the ports on your fridge have a low resistance by using a multimeter after you access the relay and compressor.The compressor may need to be checked if the relay still works.
Step 1: Plug your fridge.
If you want to access the power cable, pull the refrigerator away from the wall.Someone can help you pull the fridge out if you can't do it on your own.If you want your fridge to have no power, you have to remove it from the outlet.You can keep your food safe in your fridge for up to 4 hours and in the freezer for 48 hours without power.Don't open the doors to stop it from heating up.If you expect your repairs to take longer than 4 hours, you should move your food to a different fridge or cooler.If your fridge is malfunctioning and you don't know how long it's been, you should throw away your food.
Step 2: To access the relay, remove the lower back panel from the fridge.
There is a small access panel on the back of your fridge.To remove the screws that hold the panel in place, use a screwdriver and place them in a bowl.The back panel is out of the way if you set it aside.You don't have to remove the entire back of the fridge.
Step 3: If the relay has a plastic cover, take it off.
There is a large black cylinder on either side of your fridge compressor.There is a black plastic box on the side of the compressor that has wires coming out of it.Carefully remove the plastic cover from the compressor to expose the relay inside.Sometimes it's necessary to use a screwdriver to open tabs on the plastic cover to remove it.The relay may not have a plastic cover.
Step 4: The wires need to be disconnected from the relay.
The relay is attached to the side of your compressor and has wires running to it.Attach the ends of the wires to the relay with a pair of pliers.You need to remove the relay from each wire.A wire may be attached to a screw.Before pulling the wire out of place, loosen the screw with a screwdriver.
Step 5: Pull the relay off of the prongs.
Carefully remove the wires from the compressor's prongs, and then grab the relay on the side.If you want to test it, you should remove the relay from the compressor and then use it.Push the compressor off of the prongs if you can't pull the relay easily.Don't pull the relay if you want the compressor to bend or break.
Step 6: If the relay is shorted, look for burnt marks around the ports.
If the relay has any charred marks around the ports where it plugged into the compressor, it's time to inspect it.If you see burnt parts on the relay, then it needs to be replaced.Continue testing the relay if it's still intact.If the relay is shorted, you may be able to smell char on it.
Step 7: To read resistance, set up your multimeter.
If you set your multimeter to read resistance in ohms, you can easily test the relay.You can use the black and red probes if you plug the end of the red probe into the positive terminal.A multimeter can be purchased from a hardware store.
Step 8: To check for open resistance, put the probes in the M and S slots.
The ports on the side of the relay that have the letters M and S above them are usually the ones that connect to the compressor.If you want to check the reading on your multimeter, put one of the probes into each slot on the relay at the same time.It doesn't matter which probe you put into which port.The reading should state that there is an infinite level of resistance between the 2 ports.The relay is upside-down if the reading doesn't say "OL"
Step 9: If the resistance changes to 0-1 ohms, flip the relay upside-down.
When you turn the relay over to the other side, keep the probes inside of the same ports.The relay is still functioning if the meter has a reading between 0-1.It may be time to get a replacement if the reading is above 1.When there is an electrical current running through the relay, a small metal piece moves inside.The metal piece closes the line when it comes into contact with the ports.If the relay has correct readings, you should check the compressor next to it to see if it is causing the problem.
Step 10: If the resistance doesn't read OL or 0-1 ohms, order a replacement relay.
If your reading was over 1, you will have to replace the relay.You can find the model number on the side of the relay and match it to your refrigerator.Plug the new relay into the compressor's prongs.Attach the wires back to the relay so it can turn on the compressor again.Make sure the new relay works before putting it on the back panel.You can buy replacements from appliance specialty stores.They cost anywhere from $20 to 80USD.If you can't find the model number on the relay, you should look for the refrigerator model you have to buy a piece that fits inside.If you want to make sure the cause of the problem is not the compressor, try testing it.
Step 11: The probes of a multimeter should be on the left and right side of the compressor.
The relay plugs into the side of the compressor.One probe is furthest to the left and the other on the right to take a resistance reading.You don't want to forget the measurement, so write it down.The prongs are going to be shaped like a triangle.For the first measurement, use the prongs that are horizontally across from one another.The fridge model and compressor will affect the resistance between the 2 prongs.
Step 12: The resistance is between the leftmost and the third part.
Continue holding one of the probes against the compressor.The third pin is where the other probe will either be on the top or bottom.Between the 2 prongs, take a resistance measurement.If the triangle is upside-down, the third prong will be on the bottom.The third prong will be on the top if they form a right side up triangle.Hold the probes for at least five minutes until the resistance settles on a single reading.
Step 13: The measurement can be found from the rightmost and third parts.
Move the other probe so it is on the rightmost one.To get an accurate reading, keep the probes on the multimeter for at least 5 seconds.To find the resistance measurement, check the multimeter and write it down.
Step 14: If you add the lowest two readings, you can see if they are close to the largest reading.
Add the 2 smallest resistance readings from the compressor together to find the total.Take the highest resistance measurement and divide it by the sum of the 2 readings to see how close they are.The compressor is okay if the sum of the 2 readings is less than the highest reading you took.If the readings are higher than the threshold, you need to call someone to fix or replace the compressor.If the compressor is expensive to fix, you may want to buy a new one.There may be a problem with the internal fan if the compressor still works.If you have a problem with your fridge, contact a repair person.