Dometic fridge issue

While searching earlier found a video suggesting bypassing controls to verify if cooling unit is working. Basically hooking heating unit up direct. I did this and the temp inside fridge hasn't budged. I am now convinced that the cooling unit is toast. I was hoping for something simple but no luck. Time for a new fridge. Has anyone replaced a unit themselves. This one is 13 years old. Is new unit direct replacement?
And, as always, thanks to everyone for your help.

Pull the outside grill off back of fridge vent. Attached to the back of the fridge unit is a black plastic box with a couple of screws holding lid on. Open this box up and inside will be a couple of small glass buss fuses. Fridge will not work at all if the one controlling 12v is blown. Replace them both regardless, as it is sometimes hard to tell if a buss fuse is haywire. Not always blown, but coming apart.
This was my problem a few years back when my fridge would not work.

Katdaddy wrote:

jkwilson wrote:
The easiest check IMO is to get a power cord, crimp spade terminals on it to match the terminals on the electrical heating element, and plug that in in place of the refrigerator power cord. Let it run for a day. If it is cold, that proves the cooling unit works and your problem is on the control side.

But if that is the problem shouldn't it cool on gas?

Basically you aren’t getting any cooling. Could be because the cooling unit is bad or it could be because the control side of things isn’t working. Plugging it in will let you try to figure out if anything is working. You’ve got to narrow it down a step at a time.

Did you look at the back?

enblethen wrote:
I would suggest removing the circuit board and look at it closely for burnt areas. Arcing could have damaged more then just the 120 volt AC portion.

Circuit board does not appear to have damage.

jkwilson wrote:
The easiest check IMO is to get a power cord, crimp spade terminals on it to match the terminals on the electrical heating element, and plug that in in place of the refrigerator power cord. Let it run for a day. If it is cold, that proves the cooling unit works and your problem is on the control side.

But if that is the problem shouldn't it cool on gas?

The easiest check IMO is to get a power cord, crimp spade terminals on it to match the terminals on the electrical heating element, and plug that in in place of the refrigerator power cord. Let it run for a day. If it is cold, that proves the cooling unit works and your problem is on the control side.

I would suggest removing the circuit board and look at it closely for burnt areas. Arcing could have damaged more then just the 120 volt AC portion.

Fridge has been running on gas since 3:30 yesterday afternoon. Only a 4 degree drop in temp this morning, and I think that has more to do with drop in outside temps than cooling of the unit. What to check next?

If you don't have an OHM meter (a good investment) you could also disconnect the electric heating element and apply 120V directly to it. If it gets hot it's OK but if nothing happens, it's a gonner.