Thetford fridge power board testing error 10

retiredbeep

I am trying to establish the cause of error 10 on a N112 Thetford Fridge. This means no power from the vehicle. However on testing the wire leaving the board to go to the element when the engine is running I do get a good voltage reading. How can I be sure as to the cause of the fault to replace the board is the best part of £200. The fault could be the element so how can I know where the fault is. Any help would be much appreciated. I know these boards are suspect and a update board has been made available. The present board was replaced under warranty less than 2 years ago but the van ( Lunar Clubman ) is now out of warranty as is the fridge. 

iffajobsworthdoing

My mobile engineer came out and changed the element for £30 and charged £35 labour.

retiredbeep

My problem is I don't know if the fault is the element or the power board. How do you tell if it is the element at fault?

DougS

There should be a refrigeration fault finding chart on the Thetford website.

In summary it says for error 10:

Depending on the model, it should be in manual mode.

Check DC input from the car

Check D+ (fridge supply)

9.5-15.5V is given for both.

Check 20A fuse

Replace power board

Unsure of the pin numbers on the tow bar sockets - depends if you use 13 Pin - plenty of other info.

Other option is to remove fridge vent and find 12V element, remove connections and see if it's open circuit or not plus is there a supply when car engine is running.

Rather than replace the board, if this happened to me, I have considered simply re-wiring the power board 12V element supply supply from the 13 pin socket through an in-line fuse straight to the element with an LED behind the fridge vent so it could be seen
from the outside. This would show that there is power to the 12V element and by-pass all of that electronic circuitry. As long as the engine was running, the element would be live and could be monitored?

I have a document which MAY be the circuit diagram and some hints but can't attach it

retiredbeep

I have been trying to avoid it but I think my next move is pull out the fridge and find out if the element works or not. If it is OK then replace the board. With power at the wires leading to the element you would think the element must be suspect. Thanks
for the help folks.

retiredbeep

Removed and tested the element and all OK so replaced the power board and still have error 10 and fridge not working on 12 volt. Feeling a bit lost now will welcome any ideas.

DougS

As you have followed the fault finding chart to the letter I would suggest you contact Thetford.

There is the possibility that the new board is also faulty but you obviously now deserve their support.

At May 2015 their contact number was:

Thetford Customer Service Team on 01709766752.

Hope this helps.

 

retiredbeep

Thank you DougS for the contact number. They were able to check out a few things with me and they came to the conclusion there was a faulty earth on one of the circuits. Result fridge now working again on 12 v. The only downside is I did not need to buy
the new power board but however I now have the lastest version which is suposed to be better than the old one. Thanks again for your interest.

DougS

Glad Thetford were able to help although it sounds like they need to update their troubleshooting information and you have a spare board for sale or any further repair.