PLEASE HELP - Dometic RML 8555 DEAD/No Power!!

[rdiachenko]

So this is probably my fault and I most likely did something but that being said I was very careful. I pulled the fridge (Dometic RML 8555) out to access the fridge vent for running some Pepwave antenna cables down to a router and after I put the fridge back in with no issues, I can't get power (upper control panel/display doesn't even show power and can't power on - this would seem to be an issues with the 12V as the 120V is not required for this). I took pictures of all the connections prior to disconnecting and after sliding the fridge back in, reconnected exactly as before - I've quadruple+ checked and still I can't get power. I've checked all the fuses - which for some reason seem to have none listed for the fridge - but I've pulled and checked them all anyway. I've tried the small reset button the the little thermal fuse thing without success. I've traced the power with a multimeter - it's definitely getting power from the 12V (which I found out the hard way is NOT cut off by the battery disconnect!). I traced the power through the lower control module and with some voltage changes seems to be both coming and then going out (on various pins) of the ribbon cable to the upper control panel. For the life of my I can't find an actual fuse on this thing - seems like there's very little information on the 8555 - I took off the lower control module hoping there were fuses inside (much like other models) but other than two small connection access panels, the entire unit seems to be a unserviceable molded/fused box - no way to open. I am COMPLETELY at a loss - anyone have any ideas - is there some ridiculously simple thing I'm missing here?

Thanks for the help!

RD

[ITSNO60]

I have the same fridge, there are 2 fuses but the one you are concerned with is very small, between 3 and 5 amps, that's the one that runs the board in the eyebrow. The 20 amp fuse is just for the 12 volt heating element. Both are located in your fuse box, not the fridge. The other thing is the connections inside the back of the eyebrow, If any of those got tugged on when removing the fridge they are pretty easy to unseat. You have to remove the eyebrow by opening the door and removing two screws on the bottom then pull it out of the plastic clips then unscrew the back cover. My wiring is short and there was barely enough room to pull the eyebrow back cover off and get my fingers into the back to push the connectors back together. In case you are unsure if the wires on the back are properly connected post a pic, although you sound pretty sure you put them back correctly. The tiny purple wire is what powers the board inside the eyebrow and I recall it is double lugged with another wire under the same screw on the terminal block. If there is not 12 volts on that purple wire you will get no board and the fridge won't work on any source.

[ITSNO60]

Here is a picture of my load center showing the pink 3 amp fuse which supplies power to the purple wire which powers the control board. It use to be a 5 amp but was changed to a 3 amp during a recall campaign. Your's may not be exactly like mine as mine is in a van RV, not a trailer.

[ITSNO60]

I almost forgot, there is a 1 amp fuse on the board. I have never had mine burn out though but worth a check.

[ITSNO60]

Here is a pdf of the service manual.

[ITSNO60]

Here is the wiring diagram from a different manual, this manual is from Sweden and refers to 230 volt mains voltage but the wiring is the same as our 120 volt units as it is 230 volts to neutral just like our 120 volts to neutral. Check your purple (violett) wire for 12 volts, if it is present check the connections on the back of the board and the 1 amp fuse.

[rdiachenko]

Thanks so much for the reply - I've checked all my 12V fuses in the main box - nothing blown. I doubled checked the upper control panel connections this morning as you suggested - just wanted to make sure I didn't miss anything - tightened the connections and still nothing. For my model, there actually NO small fuse on the upper control board and the power and communications are supplied through a ribbon cable coming from the lower control box (see picture). The only other incoming connectors (the two small white wires) are from temperature sensors coming from the two compartments. Still at a loss unfortunately - looks like time to throw in the towel and call for repair - I'm sure they'll probably want me to replace the main board.

[rdiachenko]

Looks like mine is a little different - no fuse.

[rdiachenko]

TOTALLY my bad, really sorry, just realized my model is a RMD not RML - revising this thread - that would explain the model differences

[rdiachenko]

This should be RMD not RML - my apologies but I can't figure out how to edit the original post - will repost with correct model.

[Lily&Me]

Might call their customer service line and see if they can walk you thru troubleshooting.

Maggie

[rdiachenko]

Okay so just before finally caving and calling for repair, I decided to check in the 12V junction box (in my 25FBT Globetrotter, located extremely inconveniently under a panel beneath one of the twin beds). This is where I previously found the redundant fuse for the propane detector repair. And sure enough, there was a little red light on a super-weird fuse cartridge thingy on the 12V junction block. Rechecked with wiring and yep, that's a refrigerator fuse - it was labeled "3 way refer" which was how I must have missed it in the diagram before). So to be clear, there are NO (at least that I can find) fuses on the actual RMD 8555 control panels or in the wiring - there is ONLY this fuse in the Airstream 12V box. Aside from this, I also had a hot wire on the 12V input so I can't really explain that but after replacing the fuse, the fridge powered on and started to cool.

This fuse was definitely NOT easy to find - the local RV Repair place had a good selection, but not this one - it's a mini cylindrical fuse 2AMP 250V (though the cartridge thingy its in says 24V - not really sure what's going on here with the voltage but I'm not as familiar with electrical as I'd like to be). After visiting a few different stores, I found the correct replacement at RadioShack and the fridge is now powered up and cooling down.

Thanks so much for all the help!

RD

[ITSNO60]

Originally Posted by rdiachenko

Aside from this, I also had a hot wire on the 12V input so I can't really explain that but after replacing the fuse, the fridge powered on and started to cool.

There is always voltage on the terminal block that feeds the 12 volt elements, which is what your 20 amp fuse powers. The 12 volts on that block does nothing else and does not even connect to anything till it gets a signal from a relay which in most cases is when you start your engine on your TV while plugged into the 7 way and the relay engages telling the automatic power selection to choose 12 volts. In other cases the 12 volt can be used manually without the vehicle input as well. The 3 volt fuse is what energizes the board and with no power to the board nothing can happen, as you found out.

[John Aspinal]

I had the same problem with no response at my eyebrow board.All fuses were good and had 12 volts up to the board.Contacted Dometic on my 2.5 year old fridge no help from them as for as warranty help cost of new board 900.00 plus tax has been on order foe 1.5 months with no delivery date in site.Not good no fridge no camping.Fridge is from Germany part expensive and not available.Does any one have one or know were to get one. Thank you

[jeffmc306]

Originally Posted by rdiachenko

Okay so just before finally caving and calling for repair, I decided to check in the 12V junction box (in my 25FBT Globetrotter, located extremely inconveniently under a panel beneath one of the twin beds). This is where I previously found the redundant fuse for the propane detector repair. And sure enough, there was a little red light on a super-weird fuse cartridge thingy on the 12V junction block. Rechecked with wiring and yep, that's a refrigerator fuse - it was labeled "3 way refer" which was how I must have missed it in the diagram before). So to be clear, there are NO (at least that I can find) fuses on the actual RMD 8555 control panels or in the wiring - there is ONLY this fuse in the Airstream 12V box. Aside from this, I also had a hot wire on the 12V input so I can't really explain that but after replacing the fuse, the fridge powered on and started to cool.

This fuse was definitely NOT easy to find - the local RV Repair place had a good selection, but not this one - it's a mini cylindrical fuse 2AMP 250V (though the cartridge thingy its in says 24V - not really sure what's going on here with the voltage but I'm not as familiar with electrical as I'd like to be). After visiting a few different stores, I found the correct replacement at RadioShack and the fridge is now powered up and cooling down.

Thanks so much for all the help!

RD

RD, are you talking about the red parts that look like jumpers in the block pictured? If not, where is the fuse you’re talking about?

I took photos of the inside of the 12V junction box when replacing the old Atkinson solar controller last summer.

Thanks!
Jeff

[rdiachenko]

Hey Jeff,

The big red fuse is actually the 1AMP blade fuse (good luck finding that if you ever need it - had to order special from AMZ) for the propane detector (yes ANOTHER fuse in addition to the cylindrical in-line fuse which is closer to the detector (ALSO a 1AMP - but cylindrical - which is ALSO very hard to find).

I assume the smaller blade-like devices in the block are just jumpers/shunts - I believe I removed these before in troubleshooting the propane detector and found no fuse in them.

The refrigerator fuse is actually in the black cartridge-like device at the end of the block (same block as the jumpers). It's labeled "24V" for some reason - not sure why. It simply unplugs and can be opened to reveal a mini-cylindrical 2AMP/250V fuse (luckily the RadioShack in town had some). The cartridge has an LED indicator on top (which on mine was lit up red since the fuse had blown) - the cartridge has this LED and some small circuitry - it may just be to provide an indicator on this fuse. I probably would not have realized this was a fuse at all if it wasn't lit up. I referred back to the wiring diagram and it's labeled "3-way refer" which doesn't immediately prompt one to think of the REFRIGERATOR - also not sure what the "3-way" means.

Hope this helps!

RD

[acater]

Originally Posted by rdiachenko

Okay so just before finally caving and calling for repair, I decided to check in the 12V junction box (in my 25FBT Globetrotter, located extremely inconveniently under a panel beneath one of the twin beds). This is where I previously found the redundant fuse for the propane detector repair. And sure enough, there was a little red light on a super-weird fuse cartridge thingy on the 12V junction block. Rechecked with wiring and yep, that's a refrigerator fuse - it was labeled "3 way refer" which was how I must have missed it in the diagram before). So to be clear, there are NO (at least that I can find) fuses on the actual RMD 8555 control panels or in the wiring - there is ONLY this fuse in the Airstream 12V box. Aside from this, I also had a hot wire on the 12V input so I can't really explain that but after replacing the fuse, the fridge powered on and started to cool.



This fuse was definitely NOT easy to find - the local RV Repair place had a good selection, but not this one - it's a mini cylindrical fuse 2AMP 250V (though the cartridge thingy its in says 24V - not really sure what's going on here with the voltage but I'm not as familiar with electrical as I'd like to be). After visiting a few different stores, I found the correct replacement at RadioShack and the fridge is now powered up and cooling down.



Thanks so much for all the help!



RD

Your post helped me troubleshoot a similar problem. I was having problems with my dometic rmd 8555 fridge staying cool on propane. Eventually we got that resolved but in the process I must have made something touch and the fuse blew. The main fuse panel had nothing saying fridge. So your post let me to that same hella hard to reach dc box, where I saw the red light. Bypassed the fuse using a spade connector I had and then it confirmed that that was the culprit. Replaced with a regular 2am 12volt fuse and all working again. But I’m trying to find how to order the original fuse with the light incase it happens in future and I can’t find the part online anywhere. Anyway thanks for your post, it helped me get back to enjoying my trip.

[jeffmc306]

Originally Posted by acater

Your post helped me troubleshoot a similar problem. I was having problems with my dometic rmd 8555 fridge staying cool on propane. Eventually we got that resolved but in the process I must have made something touch and the fuse blew. The main fuse panel had nothing saying fridge. So your post let me to that same hella hard to reach dc box, where I saw the red light. Bypassed the fuse using a spade connector I had and then it confirmed that that was the culprit. Replaced with a regular 2am 12volt fuse and all working again. But I’m trying to find how to order the original fuse with the light incase it happens in future and I can’t find the part online anywhere. Anyway thanks for your post, it helped me get back to enjoying my trip. Attachment 433463Attachment 433464

We also blew that fuse by accident and took our trailer to a Dometic service center (General RV). The tech called Airstream to get a wiring diagram and eventually gave up and pulled a new wire to the WFCO distribution panel (under the fridge) and connected it to an unused blade fuse then marked it on the panel. Easy-peasy, can replace without having to get into the DC box. Might be the easier way to go. I couldn’t find that module either.

[DDR]

Did you ever find the part? In search myself.

[rdiachenko]

I was able to order an assorted kit from AMZ which had 1AMP fuses - https://amzn.to/3PP6SAy