# 12V LED not working



## moses007 (Nov 12, 2010)

Hello all; can anyone tell me how to gain access to the little LED light that should be lighting up when our Dometic fridge is on 12V.
The fridge works fine whilst travelling but the LED is not working.
Gas and 240V fine, will I need to remove the fridge from its cabinet or can this be done whilst the fridge is in position?
Hope someone out there can help.
Regards; Mo.


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## BwB (Dec 5, 2009)

Can you post the model of the fridge. There are so many variants it would be difficult to give you an idea of how to attempt a fix without knowing. 

On my own model I undo the two screws at either end of the plastic panel and then slide the whole top of the panel out towards you. Eventually you'll see the circuit boards.

Could be different on yours.


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## moses007 (Nov 12, 2010)

Thank you Bryan for your help, I will post the model number this evening.
Many thanks; Regards Mo


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## moses007 (Nov 12, 2010)

The fridge model is; Dometic
Model RM 7401 L
Type 40/110
Hope this helps.
Kind regards; Mo.


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## Morphology (Jul 23, 2010)

How good is your Greek?

Dometic Models 6290-7750

Looks like the top panel is fixed, and you pull the whole fridge out to get to the back of it?


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## sallytrafic (Jan 17, 2006)

Before doing anything I would double check that it is working on 12v after all a good fridge will keep it's low temperature for at least 10 to 12 hours if the door is kept shut and is fairly full.


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## moses007 (Nov 12, 2010)

:? Whoops! Thank goodness for pictures, thank you Morphology.

Good point Sallytrafic, we did a trip of 190 miles with the fridge packed last Friday and back on Monday the fridge seamed to keep its cool as it were, but that was only three to four hours, before I start taking the fridge out I suppose I should check a little closer.
I have no test equipment but I have read somewhere that if the fridge is working heat should rise from the upper vent on the side of the motor home, so I suppose if I set the fridge to 12Volt and run the engine for about half an hour this will tell me one way or the other. Do you agree :?: 

Kind regards; Mo


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## sallytrafic (Jan 17, 2006)

If the fridge is empty run it as you suggest with its door open you should soon have condensation from the cool part.


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## moses007 (Nov 12, 2010)

Will let you know how it goes, will try it tonight. :roll:


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## moses007 (Nov 12, 2010)

Tried fridge with the engine running for about 45 minuets, door open no condensation so not working, checked the two relays under the bonnet which I think relate to the fridge and the retracting step which incidentally has stopped retracting, the relays are pulling in and out as they should and power is coming from them, the problem must be beyond these. I see there is a relay and further connections behind the step switch just inside the main door, perhaps the main feed to the fridge passes through this. Going away this afternoon, so not able to strip this out for a day or two, but will get to the bottom of the problem at some stage in the near future. Will post my findings as and when they might be of interest to others with similar faults.

Once again thanks for all the advice I have received.
Regards; Mo. :?


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## moses007 (Nov 12, 2010)

Problem Solved.  
I will quickly go through what led to the discovery of the problem with the 12Volt supply to my fridge in case it helps other motor home owners with a similar fault.
First of all I would like to thank all, who gave advice this has helped immensely.
As can been seen from previous posts I first thought the 12volt indicating LED had packed up working, after all we had done a few trips and the food in the fridge seemed to be ok once we had reached our destination, travelling time about 4 hours in quite high temperatures, having ran the fridge for the previous 12 hours on 240volt before filling at the last minuet before setting off.
As can be seen from a previous post the question was asked, was I sure the fridge was working, as it could be possible that the contents of the fridge could still seem cold for anything up to 12 hours.
It was suggested that I leave the fridge door open and run the engine for half an hour and note whether any condensation would form inside on the cold surfaces, the engine ran for 45 minutes no condensation at all, conclusion fridge not working.
Located the fuses and relays under the bonnet, ran the engine and checked fuses, OK 12volt tester purchased, showed power going in and out of all 4 fuses, next turn the attention to the two relays pulled both out then back in again and could feel them clicking in and out, tested them with the 12volt tester, yes the switches within the relays working fine.
The retracting step had packed up working, so having read that the two i.e. fridge and retracting step are somehow linked I turned my attention to the switch and relay at the step, the step operated manually by its two way switch but wouldn’t retract automatically, I once again ran the engine pulled the step relay out then in, nothing, checked for power, nothing, now I needed answers, so being a layman I thought if I just momentarily link a wire from the step switch (live side) to the relay in effect back feeding the supply I should get a reaction, that reaction might be a blown fuse or something worse so here goes, the step buzzer sounded the step retracted and the 12volt LED lit up on the fridge, result. Now the electrically minded among you will no doubt be throwing your arms up with horror you can’t do that but I did and it proved the point. The temptation might have been to make this link wire permanent; under NO circumstances should this be done, the wire feeding the step relay is of a lighter gauge than the wire that feeds the fridge, the fridge load is a lot higher. It was looking as though I was going to have to remove the fridge to gain access to the connections in the top as the front panel of the fridge was fixed. I decided to remove the vent on the outside to see if I could gain access to the top of the fridge from there, no luck I could see the 240V supply and the 12V supply wires coming up from below and disappearing into the top, so I removed the bottom vent and there was the culprit a small connector with a feed wire coming from the relay under the bonnet, connected to the fridge and a smaller gauge wire feeding the relay for the retracting step. Poor connection here, so remade the connection and BINGO all is well.


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## sallytrafic (Jan 17, 2006)

Glad you are sorted and thanks for coming back on here with the solution its not always done


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