Which terminal is start and which is run on the compressor, there not marked/labeled

This is a bit complicated. Turn off power by unplugging it or turn off breaker/disconnect. On the comp you have 3 terminals, C, S, R. (Common start and run). You need to mark, label, or write down what wire goes to what terminal(red to run, black to common.....ect. Remove all 3 wires from the comp. Using a volt/ohm meter set to the ohms position, measure the resistance between common & start, common & run, run & start or C to S, C to R, R to S. All three readings should give a different reading. If all terminals are equal readings or if any terminal shows open or (infinite resistance) then the comp is damaged. Also test each terminal to ground by touching 1 lead to 1 terminal and the other lead to metal housing of unit ensuring you are touching metal and not paint. If any terminal shows a reading, other than infinite, to ground then the compressor is damaged.

HI. This will essentially be the result of a failed compressor start relay, or the compressor itself may be damaged, as well. I will lay out a procedure that will help diagnosis the situation. Please reply with the correct model number and brand for accurate part numbers, if possible.
Procedure:
THE RELAY

The compressor relay starts the compressor. A fault relay can result in the compressor failing to cycle on. The relay is accessed from the lower rear of the refrigerator. The compressor relay can be accessed by removing the terminal cover box. The cover is held on by tension or with a retaining clip. On soem units. the relat may not be covered at all.(each modle may vary). Benethe the terminal cover(if equipped), you will find the compressor relay, and the overload protector as well. The electrical terminals of the commpressor motor are loctaed here also. Remove the compressor relay by pulling it straight off from the compressor, gently. Pull the wire off of the side terminal of the relay. It is connected with a slip on connector. Firmly pull the connector, do not pull on the wire. You may need to use a pair of needle-nose pliers. Inspect the connector and terminal for corrosion. If either is corroded they should be cleaned or replaced. There are two types of relays you may encounter, wire coil and solid state. If the relay has an exposed wound wire coil it can be tested for continuity. Otherwise, the relay is of solid state design and requires specialized equipment for testing. Test the relay with a ohm(multimeter), for continuity. Set the meter to the ohms setting X1. With the relay upside down, place the probes into the terminals labeled "S" and "M"(the labeling may vary on each modle). The meter should display a reading of zero ohms, indicating continuity (or if using a continuity tester, it should light up). With the probes still in place, turn the relay over. You should hear the click of the magnetic switch engaging. The meter should now display an ohm reading of infinity (or the tester should not light up). Turn the relay upside down again, place the probe on the "S" terminal and place it on the side terminal labeled "L". The meter should now display a reading of zero ohms (continuity). Turn the relay over and the reading should change to infinity. With the relay upside down place one probe on the "L" terminal and the other probe on terminal labeled "M". The meter should display a reading of zero ohms. Turn the relay over and the reading will stay the same, zero ohms. Now, if the relay fails these described tests, it shohdl be replaced asap.

COMPRESSOR TEST PROCEDURE


The compressor is accessed from the lower rear of the refrigerator. Generally the same proxsimity of the realy. The compressor motor can be accessed by removing the terminal cover box. The cover is held on by tension or with a retaining clip. The main testing points will be the actual terminal post that hold the relay, gently pull the relay of the terminal box on the side of the compressor, and use the relay holding probes for testing. Once the relay is removed, Place one probe on any terminal and then touch the other probe to each of the other two terminals. The multimeter should display a reading of zero ohms. Be sure to set your meter to 1X before begining. Now move the first probe to a different terminal and test the other two terminals with the other probe. Finally, move the first probe to the last terminal and test each of the other terminals with the other probe. Every test should have continuity with the multitester displaying zero ohms. If the compressor motor does not pass all of these tests, the compressor will require professional service. Now test the compressor for ground. With the multimeter still set to X1, touch one probe to bare metal on the compressor housing (it may be necessary to scratch away a little paint to expose the metal). Touch the other probe to each of the three terminals in turn. None of the terminals should have continuity; the multitester should display a reading of infinity. If any of the grounding tests show continuity, the compressor will require professional service.

The compressor relay's purpose is to start the compressor. A faulty relay can result in the compressor failing to cycle on. The relay is accessed from the lower rear of the refrigerator.
Before testing a compressor relay, unplug the refrigerator to avoid an electrical shock hazard. Also, if the compressor uses a capacitor, it must be discharged first to avoid the risk of electrical shock.
The compressor relay can be accessed by removing the terminal cover box. The cover is held on by tension or with a retaining clip.
Beneath the terminal cover is found the compressor relay (labeled "A" below), overload protector (labeled "B") and the electrical terminals of the compressor motor.
Remove the compressor relay by pulling it straight off from the compressor.
Pull the wire off of the side terminal of the relay. It is connected with a slip on connector. Firmly pull the connector, do not pull on the wire. You may need to use a pair of needle-nose pliers.
Inspect the connector and terminal for corrosion. If either is corroded they should be cleaned or replaced.There are two types of relays you may encounter, wire coil and solid state. If the relay has an exposed wound wire coil it can be tested for continuity. Otherwise, the relay is of solid state design and requires specialized equipment for testing.



Test the compressor relay for continuity using a multimeter. Set the multimeter to the ohms setting X1.
With the relay upside down, place the probes into the terminals labeled "S" and "M". The multimeter should display a reading of zero ohms, indicating continuity (or if using a continuity tester, it should light up).
Turn the relay upside down again, place the probe on the "S" terminal and place it on the side terminal labeled "L".
The multimeter should now display a reading of zero ohms (continuity). Turn the relay over and the reading should change to infinity.
With the relay upside down place one probe on the "L" terminal and the other probe on terminal labeled "M".
The multimeter should display a reading of zero ohms. Turn the relay over and the reading will stay the same, zero ohms.
If the compressor relay does not pass all of these tests, it should be replaced.

You did not include a model number so this is a generic response that hopefully is of some assistance. The clicking noise your hearing is the compressor cycling trying to start.
Reasons it may do this:
1. Brief power outtage of less than 5 minutes. (Unplug and wait 30 minutes if so)
2. Compressor not starting at all (causes)
a. PTC Relay failure
b. Run capacitor failure
c. Locked compressor rotor (I.e failed compressor)
d. Heated terminals or wiring problems near the compressor

A technician would do the following
1. Read terminals R & S to terminal C on the compressor (winding continuity checks)
2. Read terminals R and S to the case of the compressor (checks for internal compressor short)
3. If the above tests pass he or she would replace the PTC relay, Kilxon thermal overload & the run capacitor. If the compressor started repairs would be complete at this time. If not see step 4.
4. Perform and amperage check comparing the Locked Rotor Amperage (LRA_ amperage on the compressor label to the actual amperage reading. If it fails this test the compressor has to be replaced.

These are the basic steps for an AC voltage compressor. Should your unit have a DC compressor the steps are slightly different.

Thanks for choosing FixYa,
Kelly

Check the compressor relay.

How To Test the Compressor Relay The compressor relay's purpose is to start the compressor. A faulty relay can result in the compressor failing to cycle on. The relay is accessed from the lower rear of the refrigerator. In the photo below the compressor is labeled "A", the relay is located in the terminal box which is located at the position labeled "B".



Beneath the terminal cover is found the compressor relay (labeled "A" below), overload protector (labeled "B") and the electrical terminals of the compressor motor.

Remove the compressor relay by pulling it straight off from the compressor.

Pull the wire off of the side terminal of the relay. It is connected with a slip on connector. Firmly pull the connector, do not pull on the wire. You may need to use a pair of needle-nose pliers.
Inspect the connector and terminal for corrosion. If either is corroded they should be cleaned or replaced.


Test the compressor relay for continuity using a multimeter. Set the multimeter to the ohms setting X1.
With the relay upside down, place the probes into the terminals labeled "S" and "M". The multimeter should display a reading of zero ohms, indicating continuity (or if using a continuity tester, it should light up).

With the probes still in place, turn the relay over. You should hear the click of the magnetic switch engaging. The multimeter should now display an ohm reading of infinity (or the tester should not light up).
Turn the relay upside down again, place the probe on the "S" terminal and place it on the side terminal labeled "L".

The multimeter should now display a reading of zero ohms (continuity). Turn the relay over and the reading should change to infinity.
With the relay upside down place one probe on the "L" terminal and the other probe on terminal labeled "M".

The multimeter should display a reading of zero ohms. Turn the relay over and the reading will stay the same, zero ohms.
If the compressor relay does not pass all of these tests, it should be replaced.

Locate the Run terminal on the compressor ( marked R ) that wire goes to one side of the run capacitor usually has a mark ... the other wire will go to the common bar on the selector switch. On the other side of the capacitor goes the Start Terminal of the compressor No other wire goes with that just one wire from ( S ) on compressor to capacitor. Hope this keeps you cool!

Since the fan is running the that eliminates a lot of stuff. You can start by checking the capacitor for the compressor. It can be checked with a multimeter with a capacitor test function. Some capacitors have 2 terminals and are only for 1 component and some have 3 terminals and are for the fan and compressor. If it has 3, they will be labeled fan, herm, com. You would put the meter leads on the herm and com terminals because that is where the compressor will be hooked up. If the capacitor is good then you need to use the resistance function on the multimeter and check the compressor windings. The connections on the compressor are labeled R, S, C for run, start, common. Connect one meter lead to C and the other to R and read the meter. Then move from R to S and read the meter. The resistance from C to S should be greater than C to R. Neither should be less than 1 and neither should read open. Hope this helps. Let me know what you find.

Before attempting any of these recommendations, First disconnect all the power sources and check your wiring diagrams on the motor and condensing unit.
On the old capacitor if you look on the top near each of the three terminals. Are they marked, fan - C - herm? If they are that is a dual capacitor and that needs to stay because that is also your compressor capacitor.
The Red wire from the conductor is Run and it's connected to C on the old capacitor.
Follow the Yellow wire and see if it goes to the S or start terminal on the compressor, if it does then that is the Start wire for your compressor and it connects to herm on the capacitor.
For the fan motor a lot of times the wiring connections are printed on the motor label.
Check the label, Purple should be run and connect to C on the old capacitor.
Black should be Common and it connects to the opposite side of the contactor as the Red wire. If the Red wire connects to T1 then the Black wire connects to T2.
The Brown wire shoud be the start wire on the fan motor and it connects to the Fan terminal on the old capacitor.
Now if you want to use the new fan capacitor. Take the Purple wire from the motor and look for any marks (red paint or a dash) on or beside the terminals on the new capacitor. If there is an identifying mark then connect the Purple wire to that terminal, if no marks you can connect it to either terminal. Then you need a jumper wire from C on the old capacitor to the purple side of the new capacitor. Then take the brown wire and connect it to opposite terminal of the new capacitor.

The compressor has a safety switch under the cover where the wires connect to it. That's what is kicking out. You should check the capacitor connected to the start winding. Check the wires where they connect to the compressor. A burnt off wire for the run terminal will cause these symptoms. If that's all good, it's being fed correctly on all 3 terminals, the compressor has stalled and will probably never start again. You can try a "hard start" kit, but not on a Scroll compressor (read the label). They aren't designed to survive that.