12v fridge fuse, 2014 Stanton

Part way through a 2 week trip to  Brittany and our Dometic fridge isn’t cooling when driving. Am I correct in thinking that there will be a 12v fuse somewhere near to whichever battery supplies the fridge? If so, which battery is it and where is that fuse located?
I’ve looked at the fuses in the EC500 unit but there doesn’t seem to be one for the fridge.
While I was there I noticed that the green “Charger” light wasn’t illuminated, should it be and could this have anything to do with the fridge issue?
Had a look at the archive but couldn’t find an answer there; hopefully one of you can give me a steer!

Thanks.

There should an additional small black/grey box em40/50 with about 4 fuses in it. Don't know where located on a Stanton, perhaps under a bed. Is your ec500 under a bed, in which case the extra box will likely be there as well.

Hi Paul, thanks. I already checked the two fridge 20A fuses in the EM40 unit, both OK. 
I suppose that the 12v “heater” in the fridge may have packed up (not unknown, apparently) but I’m now more puzzled why the Charger green light is not not on! The book says it is fed via fuse 15, which is internal to theEC500, rather than being one of the 14 in the array. I’m not about to take the top off the unit on holiday!

Is any charge from the mains charger still reaching the batteries, despite being connected to an EHU with the green charger button IN but not lit?  This is fairly easy to check by observing the battery voltage when there is no solar charge e.g. at night time or by covering the solar panel in the day time.

Caraman wrote:Is any charge from the mains charger still reaching the batteries, despite being connected to an EHU with the green charger button IN but not lit?  This is fairly easy to check by observing the battery voltage when there is no solar charge e.g. at night time or by covering the solar panel in the day time.

Just jumped out of bed before it gets light here in France! Yes the panel indicates that both batteries are being charged from the mains.

Pete Taylor wrote:

Caraman wrote:Is any charge from the mains charger still reaching the batteries, despite being connected to an EHU with the green charger button IN but not lit?  This is fairly easy to check by observing the battery voltage when there is no solar charge e.g. at night time or by covering the solar panel in the day time.

Just jumped out of bed before it gets light here in France! Yes the panel indicates that both batteries are being charged from the mains.

So if the battery is showing over 13v without any solar charge, that's a good thing.  This suggests the green light in the charger switch has failed but I can't see how this could relate to the fridge.

Fridges receive their 12v cooling power from the vehicle battery via the EM40 but only when the alternator is kicking out charge i.e. when the engine is running.  I don't have your fridge but it appears its cooling power is manually switched from 12v to mains to gas.  When switched to 12v its LED will flash to indicate it is not receiving any power, until the engine is started when it should stay on constantly.  Is this how your fridge works and is it continuing to flash when the engine is running?  Remember to disconnect from the EHU before starting the engine.  If it is continuing to flash with the engine running and you have checked all the fuses on the EM40 it could be the EM40 itself that has overloaded and burnt out.  This is a common fault.  It happened to me and I had to replace the EM40.  Of course it might not be the EM40 and could be a fault with the fridge.

Caraman: it should work exactly as you described. When the fridge is manually switched to 12v and the engine started, it continues to flash and beep.
I cannot think why the lack of a green charger light would affect the fridge either.
As we are catching the ferry tomorrow and then an overnight stop in Devon, I’m going to just run through all the fuses again and then put up with the lack of fridge, when driving, until we get home.
Thanks for your help.

I think you may have had the wiring connection for the fridge in the back of the EM40 fail due to overheating and poor connection.
The fuses will be fine but have no output from the fuse out terminal to the fridge loom as it has burned out.
Remove the four small screws and ease it out to check is a five minute job.

Also check voltage at DC input terminals on fridge (perhaps behind fridge vent?). If you have 12 volts + with engine running (and should be about 13.3 volts + alternator output voltage) then you have a fault within the fridge. If not the fault is in the supply, probably the EM40.

Also if your hab step auto retracts when the engine is started then that suggests that the D+ signal to the EM40 is working OK, so narrows it down even further : to the EM40 probably.

When our EM40 went, there was an antiseptic smell which we thought at first was coming from outside.  There was nothing obviously wrong with the EM40 until I found I couldn't get the green fridge plug out.  The plastic had melted welding it in.  This was only apparent when I removed the PCB which was also damaged.  The failure of the EM40 threw up other faults but not the green mains charger button.  If the EM40 is the problem, it's easy to replace. I fitted one of these:

https://www.apuljackelectronics.co.uk/Product.aspx?ProductID=926&strReferer=search&PPGR=0