I never had both power sources connected at the same time. Dometic has sent me a new 12/24Vdc power cord as a fix. I have yet to test it, probably this week end. I am wondering if there is something in the power control board that is causing my issue.
I think from memory when both leads are connected the AC power send back through the DC circuit and kills the DC side of the electronics, With my ARB's I can leave both leads hooked up at the same time,
Many people lately have said they about plugging one lead in at a time but that defeats the objective of owning a 4x4 fridge because when a person is at home keeping the AC and DC leads plugged in allows the DC to kick in when ever there is a power outage and the same when you are on a Camp site when you hook up to shore power where it switches from DC to AC, If the Duel circuits are not paired then in either situation then a certain amount of messing around is involved and in either situation forgetting to hook up the other power source and removing the other could result in ruined food or a blown up fridge, Knowing this stopped me from buying one of the new CFX3 series,
I'm not knocking Dometic because I own a lot of their gear and it is fantastic stuff but the CFX3 falls short compared to the other Dometic Products I own, The things that worries me most of all is that Dometic's way of solving this design fault is to put a sticker telling the user not to plug in both leads at the same time, That's not fixing the problem, that's covering A$$es and tells me that they are quite happy to let it slide and have no intension of fixing the problem and are quite happy to keep selling Defective Fridges,
Every other Brand of Fridge on the Market works with both leads plugged in and So does every other Dometic Fridge Prior to the CFX3 range of fridges, Their lack of Openness and lack of Info it seems like they just don't care,
Personally I think this problem is a result of them having stopped using the Danfos / Secop Compressors in favour of their new own brand compressor, either way nothing comes close to the Danfos / Secop or the Sawafuji Compressors and Dometic should not of tried to fix what was not broken.