intermitant electrical failure

Hello - new member here - new to campervans after canal boat - love my duetto but i have a strange problem. The last few times i have tried to start the van everything shuts down no power anywhere them it all comes on again and everything is fine. Have checked all battery connections under the seat any idea what i should check next. Have thought it could be the sigma alarm or an isolator some where or a bad earth. The batteries are fully charged and the wiring seems to be in good condition

Engine earth strap?

I guess by "everything" you mean all of the lights on the dash and in the cab (i.e. the Ford part of the vehicle)? As above, or another likely culprit is the ignition switch.

Were would I find engine earth strap

Sorry, can't help specifically. From engine or gearbox to a chassis rail, braided strap?

PLOUGHLIN wrote:Engine earth strap?

If as well suggested it's the earth strap then check your accelerator and c!itch cables as they can carry return current and quickly deteriorate or even melt.

It is a fairly common practice to fit an extra earth strap (quality battery lead will suffice) between the engine/gearbox and the vehicle chassis as they often fail without visible signs.
I have not got around to it yet so its bound to fail.

Thanks for all your great replies and I took it into a garage under warranty and luckily it lost power at the garage and it was quickly diagnosed as a badly fitted negative connection on the battery which looked OK but needed tapping down to get a good circuit. He said an earth strap fault would have failed more often but the bad connection would fail under pressure. I hope this is an end to the problem as the rest of the vehicle is excellent and so beautifully put together