Dometic RM 2652 won't cool on A/C

Fuse on board? Loose or broken wire which would be my first guess, including a bad connection.

Have you done any Voltage checks for the 120V AC circuit?

Did you use the 'correct' replacement lower control board?
Based on Serial Number -----


AC MODE:
Check that incoming 120V AC voltage is present at terminals J5 and J6 on the circuit board.
Check for 120V AC voltage at the heating element connection terminals J7 and J8 on the circuit board.
If no voltage is present, check the 5 amp AC and 3 amp DC fuses.

FUSES
The 3 amp DC fuse is designed to protect the circuit board from internal shorts. (Horizontal fuse---mid position on board)
The 5 amp AC fuse is designed to protect the integrity of the AC heater circuit from short (Vertical fuse---far left position on board)


Even when elements OHM correctly they can still be faulty.
Unplug element leads from board
Plug them DIRECTLY into the 120V AC Outlet and let it run.
This bypasses ALL controls/safety features BUT will test elements heating ability.
Plug it on in AM and check it in PM...if element works fridge will be cold

Throwing parts at it will work eventually.......testing/measuring is less costly

No expert here, you did not mention thermostat or thermostat wires?
If you unplug the wires from the 110v heating element, you can rig a direct plug and plug directly into 110v source. Wait about 10 hours or more and check to see if frig is cold (you are bypassing everything to check the element).

Also, Check with Ford's RV Refrigerator Service
Check Fords youtube channel.
If you call Ford, have all of the frig info handy.
List of what you have checked.
He will charge you for his time.
I have used him in the past.
Good luck and hope this is helpful!
Pat

Edit: I see Biscuit suggested some of the same stuff.

My original board and element were zapped in a storm. I had them tested by a friend who does A/C and refrigeration. That's why I'm stumped as to why it won't sense the A/C. I'm going to try the bypass wiring suggested. Thanks for the input, I'll run down the ideas suggested.

Old-Biscuit has given you a clue and your new little fact has me convinced that you have a thermal induced open. It doesn't take a direct strike to an appliance to cause a connection to degrade to a point where it still looks good and tests good with an OHM meter but has a resistance not noticed when cold but opens when current flow heats it up.

We had a strike somewhere in our former condo complex that took out a lot of video equipment and our 240vac element in our water heater. The water heater worked flawlessly until, someone took a shower. After finishing a shower, if someone else took one immediately, warm water only and then cold. Sometimes it took hours before the heater would work again. The problem was an open in the upper heating element. It measured correctly when at rest but after use the open would open and closed as it got hot and cooled.

I'd recommend, checking not only the connectors to the board but how solidly connected each lire is to the connector.

Good luck in finding the problem, it is very hard to find some of these electrical gremlins.

Old-Biscuit has given you a clue and your new little fact has me convinced that you have a thermal induced open. It doesn't take a direct strike to an appliance to cause a connection to degrade to a point where it still looks good and tests good with an OHM meter but has a resistance not noticed when cold but opens when current flow heats it up.

We had a strike somewhere in our former condo complex that took out a lot of video equipment and our 240vac element in our water heater. The water heater worked flawlessly until, someone took a shower. After finishing a shower, if someone else took one immediately, warm water only and then cold. Sometimes it took hours before the heater would work again. The problem was an open in the upper heating element. It measured correctly when at rest but after use the open would open and closed as it got hot and cooled.

I'd recommend, checking not only the connectors to the board but how solidly connected each lire is to the connector.

Good luck in finding the problem, it is very hard to find some of these electrical gremlins.