Dometec 3-way refrig

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I'm new to this forum, but I have no idea where to turn at this point.
I have Dometic 3-way refrigerator in my Alaskan camper that petered out on me.  I
I changed the battery which has a trickle charger plugged into it, so the battery is charged
I changed the upper and the lower circuit boards to no avail.
When I turn it on it goes to the DC power and nothing else, the gas nor the AC power comes on.
The DC power is not making the freezer cold after two days in that position and  I'm out of options.

Can anyone help me with this?

Bill
 
If you have not found it yet, take a look at this page http://dave78chieftain.com/Technical.html there is a lot of good rv refrigerator information there
 
What model Dometic?  There are several 3-ways models.

Most such fridges auto-select 120vac power if available and LP gas if not. 12vdc is a last resort cause it sucks a lot of amps to get any cooling at all. Have you verified that 120vac is actually reaching the fridge? And that  the AC power fuse on the fridge circuit board is not blown? What does the LP burner do if yu force it to LP gas mode? Any attempt to light? Is the gas line on and LP gas reaching the burner?
 
Model number RM2354
This fridge goes to DC only in auto-select, it does not light up the AC light except when first turned on, all lights go on for a short while.

Not sure if the 120vac is actually reaching the fridge.  No fuses are blown, that was the reason I ended up buying and replacing both circuit boards one at a time.

Forcing it to LP gas mode lights up but no igniter sounds comes on, the gas is on at the tank, and I bled the line of air by lighting the stove. 
Not sure if the LP gas is reaching the burner.  The only thing left, that I can think of is the cable between the upper and lower circuit boards. 

Thanks Gary 
 
Download the RM 2354 Diagnostic Manual at http://www.fourwh.com/NewDometicRefrigeratorManual.pdf

I think you first need to assure that 120v and LP are present and then figure out why they are not being recognized. Since DC mode is working, the odds are good that the circuit boards and cable are fine. Before throwing more parts $$ at it, check for proper AC voltage at the outlet the fridge is plugged to. If present there, use a voltmeter to check for 120v power at the circuit board (there is a fuse on it for the 120v electric heat element). If the AC fuse is blown, it will not detect or use 120v power.  There is also a non-replaceable thermofuse built into the cooling unit to prevent dangerous overheating. It should be checked for continuity. On some versions of the 2354, the thermofuse has a reset switch.
 
If I read the original post correctly the fridge is not getting cold on DC either, so DC mode is not working
 
He said 12v mode activates but the freezer isn't chilling.  Not clear if that means "not working at all" or just "not very cold".    The DC mode won't do much cooling at the best of times and typically does not handle a warm fridge very well.
 
Yea, DC does not work either, although, that is where the light stays on when in auto-mode. It's dead, nothing cools.

I will check the 120v but the LP is not present, although, the gas is on at the tank and no igniter sound is heard when in gas-mode.  The light just stays on at GAS. It's dead nothing happens.

Now this is new to me,
"There is also a non-replaceable thermofuse built into the cooling unit to prevent dangerous overheating. It should be checked for continuity. On some versions of the 2354, the thermofuse has a reset switch." Now where to fine the reset switch for the thermofuse?  I will need to buy me a continuity tester and figure out how to use it  before I  can tell you what's happening here but I feel good we are heading in the right direction.

It's nice to have guys like you to give me some idea on what to do.  I thought for sure I'd have it fixed with two new circuit boards. I will let you know my results when completed. 

Thanks so much,

Bill
 
The service manual I linked for you will show where the thermofuse is, and its reset if there is one. That's where I got the information about it.

OK, so there is no cooling at all in 12v mode? And if you force it into LP Gas mode, it shows GAS on the display but no attempt to ignite the flame?  In 12vdc mode, can you feel any warmth at the cooling unit boiler?  It should be getting quite hot there, and warm throughout the rest of the tubing.

120vac electric and 12v DC electric are the two simplest modes of operation, so I would do diagnosis based on one of those. The circuit board doesn't have to do much in either case except monitor the thermostat (the thermocoule on the fins inside) and switch the power relay On/Off as needed. If you can get one of those working, you are on the path to complete success.

 
And when you finally throw up your hands in disgust with that 3 way fridge, just yank it out and replace it with a Dometic AC/DC compressor fridge.  Something that should be standard in all campers instead of some goofy old school propane stuff.  I have one of these Dometic RV compressor fridges in my semi truck.  Been using it 24/7 for the last 904,000 miles.  Never gets shut off year round except to pull and clean the cooling fins.  Only runs on DC.  Freezer goods stay nice and frozen, dairy and other stuff in the fridge nice and cold.  Nice even cooling throughout.  On DC, it uses an average 3 amps per hour.  Basically the same thing as one has in their home but smaller.

Oh, and the Dometic compressor fridges?  No need to be level.  They work up to 35 degrees off level.  Try that with one of those 3-way absorption versions.
 
Madcow, this may work for you, but may not be good for people that do a lot of off grid camping as they have to generate those 3 amps per hour some way.  With solar you would be looking at something in the 200-300 watts worth of panels size range, either that or running generator for a few hours per day to recharge a battery bank.  Either way for many people a pound or so of propane per day seems economical.
 
I had a that single door fridge in my older lance. It did not work when I bought the camper, but the camper was priced according with that being a major issue. The cooling tower was bad. I was able to buy a new cooling tower for about 400. Also replaced the control board. Found out the 12v heating thermocouple was bad also, but I left in place, because of the power draw running 12v, I was ok with it being a two way, 120v or propane. Check to see if you have power to your thermocouples, they should be next to each other, but know which one your test so you have your multi meter set for the right voltage.  The propane flame can be seen in the small box with a peep hole. If your not hearing the relay click, check to see its receiving power also, it may be gummed up or a bug nest in the line.  Also, before you decide to pull it, measure your door, mine would not fit thru the door and I had to rebuild the fridge on the dinette table, guess they installed it first as the camper was being built,,,gregg
 
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