No 12V on fridge

sydnsue

sydnsue

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I have a Thetford fridge/freezer and it has stopped working on 12V. Neither manual or auto will work. It works fine on gas. Haven't had a chance to try it on 240V yet as we wild only. Have checked the 30A fuse which is fine.
Is this a visit to an expert or may there be a simple fix?
 
sydnsue said:
I have a Thetford fridge/freezer and it has stopped working on 12V. Neither manual or auto will work. It works fine on gas. Haven't had a chance to try it on 240V yet as we wild only. Have checked the 30A fuse which is fine.
Is this a visit to an expert or may there be a simple fix?
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You say you have checked the fuse ... have you actually check the voltage at the fuse output? being a three-way fridge there will be a relay involved in switching the the 12V supply on. that could have failed? I would say you need to see if 12V is coming into the Fridge to know if it is the fridge itself or just the supply and something along it.
 
You don’t say what vehicle it is but I had the same a few months ago with my Hymer and it was a very small bank of fuses in the engine bay and one had blown. I took it to a repair shop near me and they told me it was the electro block and charge me £200 for the information. I sent the block away for repair for which I paid £125 to be told the block was in fine working order. I then found the fuse myself which cost 50p to replace. I demanded my £200 back but that still left me £125 out of pocket so check around carefully first, it could be something simple
 
wildebus said:
You say you have checked the fuse ... have you actually check the voltage at the fuse output? being a three-way fridge there will be a relay involved in switching the the 12V supply on. that could have failed? I would say you need to see if 12V is coming into the Fridge to know if it is the fridge itself or just the supply and something along it.
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I return home tomorrow which is where my test gear is so I will do as you say and see if there is power at the fuse. I'm sure there will be as the step is on the same fuse and that is working.
 
i had one of these yesterday , my sister's. if you trace the wires going to the 2 electric elements -2 go to the 12v , 3 to the 240v , both go to terminal blocks on top of her fridge . it's a simple matter to check the continuity to each element.no continuity, element knacked . so her 240v was no good , £30 on e bay .ask for more detailed explanation if you need it
 
mr brown said:
i had one of these yesterday , my sister's. if you trace the wires going to the 2 electric elements -2 go to the 12v , 3 to the 240v , both go to terminal blocks on top of her fridge . it's a simple matter to check the continuity to each element.no continuity, element knacked . so her 240v was no good , £30 on e bay .ask for more detailed explanation if you need it
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If it was the element, surely the display would still show the battery symbol. It wouldn't know the element was gone would it?
 
If fuse is good then most likely to be the relay.
As stated- - run engine and check voltage at fridge.
It could be the element of course and when you get home you can check the resistance - should be fairly low. Failed element will be very high or open circuit.
 
Thanks for your comments but how do I get into the wiring to check the power? I have the N175 tall fridge/freezer. Do I need to remove the fridge to get into the back? If so is it just a question of removing the fixing screws and pulling the whole thing forward? Just concerned on how the rear vents are attached.
 
UPDATE - I opened the distribution box which is a CBE DS-520EX. The connector block which inludes the connections for the fridge has a burnt wire and the pin has completely disintegrated. I assume the whole printed circuit board will require replacement which looks expensive. The big question is what caused this? I think I still need to run a 12V to the fridge to test it but not sure how. I wonder why the fuse did not blow.
 
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If there is a burnt wire and damaged pin then possibly a short, a loose connection causing it to arc over a period of time or damp penetration. New units range from around £150 depending on the exact model, you’ll need the 6 figure digit after the DS-520EX to ensure you get the right one. Different manufacturers use this model with their own wiring configurations.
 
Val54 said:
If there is a burnt wire and damaged pin then possibly a short, a loose connection causing it to arc over a period of time or damp penetration. New units range from around £150 depending on the exact model, you’ll need the 6 figure digit after the DS-520EX to ensure you get the right one. Different manufacturers use this model with their own wiring configurations.
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I'm wondering if the pin and socket in the connector were not tight causing arcing. It still means a new connector block to be soldered to the PCB which I'm not sure is feasible. Don't want to pay £150 because of a simple connector block.
 
You should be able to get a repair specialist to solder on a connector block.
A loose connection would produce what you've found.
With a bit of luck the board should be ok.
 
Markd said:
You should be able to get a repair specialist to solder on a connector block.
A loose connection would produce what you've found.
With a bit of luck the board should be ok.
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I'm waiting on a phone call tomorrow from a motorhome repair man for exactly that. Fingers crossed.
 
Let's hope so or a local computer repair shop?
They may have soldering skills or know someone who does.
A few years ago (not that many) I found a radio/HiFi repair place to do an interior light repair.
 
UPDATE - I saw a local motorhome service company who have said they can solder a new connector to the board. Thought about doing it myself but they reckon £100 so not worth the hassle. At least they can test the fridge as well just in case. He reckoned it was just a loose connection in the connector that was arcing. 30A circuit so not surprising.
 
That's good.
These circuits do carry quite a load - really the external connection shouldn't be on the board itself because of how tight the screws need to be and fitters shying away from applying too much force.
My older dometic has the connector on the 'chassis' of the fridge.
 
That's good to hear - might be worth double checking tightness of screws after a few trips to ensure vibration hasn't loosened them.
 
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