Turn off breakers, disconnect ALL power, 110v, 12v and Gas to refer (or camper) before replacing element(s).
Split into two parts; replacing heater element and showing the Dometic recall fix. As I didn't think to take pics until after I got half way thru this lot of pics are duplicates. Its very simple change out, elements are +/-$50.
The 110 volt and 12 volt heaters (if you have a 3 way fridge) located in the refer flue are similar as far as replacing. The only difference is the wiring. The 110v heater plugs into refer board with no positive or neg, either of the 2 wires can be reattached with no regard to polarity. The 12V heater does have a positive and neg, so if your changing note which board terminal is positive.
This assumes you have already determined your heater element is bad. This page is only to show what's involved. In looking on line I found everything from "its a 10 min job" to "you have to pull refer". So hopefully this gives you idea and yours is this easy. Our 110V element simply broke where the wires are attached to heater. You can easily check continuity with a meter by removing board cover (power is off?!), unplugging the heater wires (2) from board, check the wires going to the element. There should be continuity, if no continutity heater is burnt. Ill include a link to pdf file, you can check the ohms if you have continuity but still think the heater element might be your problem.
link to dometic pdf at Bryant rv for resistance numbers. Generally the 110v heater will show approx 44 ohms +/- 10%, 12v heater will be 0.6 +/-10%.
Bryantrvsupport libary- great resource-other docs if you have a different modle.
Generally the 110v element wires attachment points to element are encased, ours was a flexible rubber and wire terminals inside broke. (Another story but broke due to installed Dometic refer recall fix, the retro fitted sheet metal flame guard was touching the element wires encasement at element, when external cover was installed it forced the sheet metal against the connection and broke them . The replacement I got is hard plastic encasement so flexing should not be a problem, plus I cut a 1/4" from flue to rotate the elements so they wont touch. I also trimmed the flame guard.) On the 12v heater elements the ground is generally an exposed spade connector and they can and do corrode.