Fridge not working from engine
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r4dent
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Most 3 way fridges do not cool down on 12v. 12v is used to slow down the warming up process on fridges that are already cooled.
Might be getting the meter out and checking if you are getting 12v with the engine running
Also check the alternator wire hasn't come off the alternator D+
and also check the supply wire for fuses.
Has it ever worked?
Might be getting the meter out and checking if you are getting 12v with the engine running
Also check the alternator wire hasn't come off the alternator D+
and also check the supply wire for fuses.
Has it ever worked?
wildebus
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Do other things that should work/stop working when you start the engine? If you have a step, does it auto-retract on engine-start still?
Possible reasons apart from the Fridge itself:
D+ (Engine Running) signal from Alternator not working (fuse?)
This would activate the Fridge Power relay - (Relay failed? In-Line Fuse?)
I would get a meter out and check the 'Heavy' +12V supply at the back of the fridge (accessed from lower vent outside) to see if you need to look at the supply side or the fridge side initially.
If there is a supply incoming, I think it might be worth removing the +12V feed to the electronics to do a full 'reboot' of the fridge electronics in case they have got confused and not resetting properly.
Possible reasons apart from the Fridge itself:
D+ (Engine Running) signal from Alternator not working (fuse?)
This would activate the Fridge Power relay - (Relay failed? In-Line Fuse?)
I would get a meter out and check the 'Heavy' +12V supply at the back of the fridge (accessed from lower vent outside) to see if you need to look at the supply side or the fridge side initially.
If there is a supply incoming, I think it might be worth removing the +12V feed to the electronics to do a full 'reboot' of the fridge electronics in case they have got confused and not resetting properly.
TJBi
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Have you tried turning the fridge off completely? While waiting in ferry check-in lanes, I once had a moho renter ask me about problems with an auto (forget which brand) that was not operating correctly. A "reboot" solved the problem.
barge1914
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Same model fridge and van. The fridge frequently started to defrost immediately on stopping, annoying amount of water to mop up. They say they checked the voltages etc. Eventually the dealer replaced the fridges ’brain’, but it still does it even in January. Let me know if you get an answer. Thanks for reminding me…I need to get another email off to them before warranty expires.
Fisherman
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wildebus
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I don't know if it will work, but with a lot of electronic kit nowadays, a long press on the power button will do a reset and restart. Could be worth giving that a go just to see?
xsilvergs
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Do you have a Roller Team with a Thetford fridge? It's hard to tell from your avatar.
Fisherman
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Yes a Pegaso 590
xsilvergs
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We have a T-Line 590 but could be similar.
With our Thetford fridge when in Auto mode it displays a battery with engine running.
Ours has a Nordelettronics control box under the left hand bench seat which houses the fuses and relays for nearly all services. Remove 4 screws for the cover reveals the connectors, the 12v to the fridge is on one of these. It is possible to measure volts at the back of this connector, these conductors (6mm2) go to the fridge and become live when the D+ goes live.
Sorry I can't remember connector number but diagrams are available on internet.
Hope this helps.
Colinsmiff
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I have a Thetford n4000, and to say it is temperamental would be an understatement. To get the 12v working I shut everything down, 240v supply, gas, van 12v EVERYTHING!! then start the engine. I then turn the fridge on select 12v manually, it works. This is the only way I can get it working. If I turn off the engine, I have to go through the whole process again. Took it back to the dealer when I first got it and he thinks it's temperamental relays, but as I can get it working 9 times out of 10 thought it best to leave it as it is.
wildebus
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mistericeman
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Same here.... 240v fridge consumes even less than our Waeco 12v cool box....Definately happy I took out the 3-way and fitted a 240V Compressor Fridge
tweaked the setup a few days ago and it works very consistantly and draws (including inverter overhead) no more than 1Ah/Hour. In the summertime would easy make up much more than that with a decent solar setup.
View attachment 105425
Barely bothered turning on at all yesterday with the low ambient...
Fisherman
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I have checked the voltage into the fridge and when I turn on the engine I get 14.6v to the fridge control. I have just found out how to check 12v element continuity which I will do tomorrow. But I cannot get into fridge control panel without an extension rod for my socket set which I have ordered. There’s a 20a fuse there which I am told is the most likely cause. So it’s either the element, fuse, or control panel. If it’s the panel or the element I will have it done under warranty. I also managed to remove the 12v fuse supply and the fault remained.
Fisherman
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Our vans fridge is live with control turned off, unlike our first van.
I removed the 12v fuse from the fuse box to disconnect from supply as advised. I waited about a minute then put the fuse back in made no difference.
I then turned engine on and got the 14.6v reading from input to fridge pcb.
I did not measure the voltage as the fridge controls all work fine, and the fridge works fine in gas or leccy.
But I now know how to check element for continuity, and I will check fuse on control panel tommorow David.
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Fisherman
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Well good news on the fridge.
I first checked the continuity on the 12v element and it was reading fine at 0.8amps.
I then managed to get to two screw bolts at the back with a 1/4 Alan key with the appropriate socket fitted on the end and undo the pcb. I immediately noticed discolouration on the pcb, and right away suspected the onboard 20 amp fuse.
And as you can see from photos it was the culprit. Put it all back together and the fridge is working on all fuels now.
My only concern is what caused such catastrophic fuse failure.
It looks like a short between the 12v and ground.
Hopefully it won't happen again.
I first checked the continuity on the 12v element and it was reading fine at 0.8amps.
I then managed to get to two screw bolts at the back with a 1/4 Alan key with the appropriate socket fitted on the end and undo the pcb. I immediately noticed discolouration on the pcb, and right away suspected the onboard 20 amp fuse.
And as you can see from photos it was the culprit. Put it all back together and the fridge is working on all fuels now.
My only concern is what caused such catastrophic fuse failure.
It looks like a short between the 12v and ground.
Hopefully it won't happen again.
Last edited:
wildebus
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Probably the fuse not seated totally and a touch loose. Those ATO fuses are not great for continuous current and get very hot. Little surprising for a circuit with limited use (only active when driving) but I had a similar issue with a fuse on the B2B circuit in my van with the fuse still ok, but the plastic melting and pushing the connector away. Chances are with a new fuse and refreshed solder, never have a problem again. ( I replaced my fuse and never had a problem since with it).