Dometic RM4605 AES fridge/freezer

Hi Peter, Yes the fridge has worked for almost one year. A bit of history... During this period I changed from a Prado to a Jeep Grand Cherokee. The fridge worked with the Prado and the auto-elec wired the Jeep and I checked his wiring and he also used a dummy board with lights to check. I have also installed solar to the van. This weekend was the first use of the Jeep towing the van and we found that the 12v DC side of the fridge not working. I have done some checking and found the 12v permanent is ok, I checked that at the fridge rear. I then checked the 12v supply wiring used to operate the logic circuit and found it working ok when the engine was running. The only problem I came across was a 20 amp fuse blown. The fuse connects the +12v supply wire to the terminal block. I replaced the fuse and it still does not work. Interestingly, the manual says it should be a 30 amp fuse.

Hi 427,

If the manual tells me it needs a 30 amp fuse and you're only running a 20 amp, I guess that's where I'd start! :-)

Anything else would need to re-checked after that!

I'm not saying that's your problem, because these faults can be a pain to track down, but a good place to start.

What kind of fuse does it run? If it's a 30AG (glass tube with two metal end-caps), I'd chuck the entire arrangement and start over - I've NEVER found them to be reliable enough for my use.

Regards,


Charlie

hi charlie
i'll second what you've said the 20 amp fuse is acting as a power restriction
it beats why someone would install a 20amp fuse when the manual states 30amp isn't that just inviting problems into an electrical circuit????

Hi mazcan,

I'm no sparky of any kind, but I'd reckon it might!

And if the unit is either borderline on its requirement or happens to draw 22 or 23 amps in operating, it MIGHT let it through without blowing, or it might not.

By the way, if I haven't said so above, I might even argue that some fuses might not be absolutely precise on their blow-point!

QED - problem!

Charlie

Hi Folks,
Many thanks for your advice on the fuse. A point to make is: The Van is almost one year old and the 20amp fuse came with the van. Funny that it worked for almost one year! I happened to noticed that the Dometic guide said to use a 30amp fuse. As I noted the fridge worked with the Prado up until recently. The replacement fuse I put in yesterday was 20 amp and it has not blown. I will replace it with the recomended 30 amp, but expect no solution to the real problem that the fridge will not move to use the 12v DC supply.

Peter

hi 427
have you checked the voltage right at the element on the fridge side of the inline fuse also if you a need a new element or anything else this site may be of use
www.rvdealership.com cheers

The model is RM4605. I have checked the 12v DC to vehicle battery and the 12v DC to house (Caravan battery's). I have not checked as yet the D+ 12v at the fridge end. The car end and caravan connection are working fine. I have the wiring diagram and will check the D+ with vehicle running/not running.
Thanks,
Peter B
Retired ICT Project Manager

Update to the last post. No 12v at the D+ fridge end but 12v at the D+ car/caravan plug. Looks like the wire has either snapped or possible burnt out somewhere. My next concern is that I will run a new wire for the D+ for the AES logic circuit but have a problem that needs to be resolved first before turning back on. Why did the 20 amp fuse (I have replaced it with a 30amp as per Dometic manual) that Dometic supplied for the 12v DC vehicle burn out? I plan to run a new wire for the D+ under the caravan but add a fuse at the rear of the fridge for this new wire. Then turn off the solar (MPPT solar controller) at the switch to ensure this is not the problem and then test the fridge. If this works I will then turn the solar back on to ensure the solar controller and the AES controller are not in conflict which could have caused the problem. If all goes to plan I should be back in business.
Thanks,
Peter B
Retired ICT Project Manager

Update 17th October. The D+ 12v is dead at the fridge. I have run a new D+ 12v wire and all is working. Thanks to all for assistance.
Peter B
Retired ICT Project Manager