Transit MK5 habitation relay

[bov783]

Hi all
Has anyone defeated the habitation relay.
My reasoning is i need the engine running to maintain the batteries
And to heat the van whilst in the habitation area.
We travel widely in areas very remote so the engine on tick over
Is seldom a problem
I can’t seem to find the relay?? It’s a 1998 Dueto on
A transit mk5 long wheel base
Many thanks
Ohol

[Altransit]

I have to ask:-

What is a habitation relay, and what does it do to stop the engine running

[bov783]

Hi
It doesn’t stop the engine but cuts power to the habitation consumer unit
When the engine is running.
It means you can’t watch tv etc if people are in the back whilst on the road !!

[dumper]

Carnot help on your relay problem but for heating the van at night you would be better fitting a night heater the Chinese one’s on EBay are reasonable price and very good I’ve replaced my Eberspacer d3 with one and very happy with it mine is run off the van tank but if yours is a coach built you could fit the tank that comes with them and run it on red diesel.

[MinorMatt]

Ok,

So this is a duetto question rather than a mk5 question. The wiring in question was added to the vehicle by autosleeper and is not a Ford part in any way.

The duetto has 2 "habitation" relays, both of which are triggered by the "charge" signal from the alternator. One has 4 wires going to it, and is a split charge relay, that connects the batteries together when the engine is running (or more accurately the alternator is charging) to allow the habitation battery to charge.

The other relay is (in my opinion) a stupid idea and what the OP is talking about. Its a 5 pin change over relay. When it doesn't have the charge signal it connects the habitation battery to the zig unit in the vehicle - allowing the rear electrics to work. When is has the charge signal, it disconnects the habitation battery and connects it to the fridge (so it only works when the vehicle is charging - which is sensible).

From memory the fridge wire is red with a yellow stripe- it will go to terminal 87 (the outer of the 2 parallel ones) and the other 2 wires are red. If you cut the wire in the middle (terminal 87A) - this feeds the ZIG unit, and connect it to the wire from the aux battery (terminal 30) this will give you permanent power to the habitation area - regardless if engine is running or not. You could also link these wires with a suitably rated switch (or switch and another relay) if you wanted to select whether you can have electrics in the back when running or not

[MinorMatt]

Oh, and on mine the 2 relays were (I have rewired it all to be more sensible and replaced the split charge relay with a voltage sensing one) mounted to the front of an additional (completely empty) auxillary fuse box attached above the underbonnet starter battery.

I am going to have a switch to allow the hab electrics to be live when the engine is running - but haven't got around to it yet. I am going to stick the switch on the dash and use an additional relay

[bov783]

Thanks for your reply, a true expert !! Let’s hope i can find the wires!
I have found the relay the smaller one of the two so will take a look.
Thanks again it’s people like you that make sites like this so important!!
Let you know how i get on !!
Best
Phil

[MinorMatt]

I only know that because I recently got a duetto and fortunately it came with a wiring diagram! I decided that the relays wern't the best design, and the empty fuse box wound me right up, so I redesigned and relocated them about 3 weeks ago