dedicated towbar wiring

[SimonS]

Hi all

I have the Westfalia wiring kit fitted and it has been working for a couple of years. However I only recently realised that you need an extension kit to power the caravan fridge . I have bought the extension kit, Westfalia part number 300025300113. Typically the instructions are minimal. Today I removed the floor of the boot and the two rear side panels, just to explore where to pick up the connections. I'm struggling to find the loom connector for the kit to plug into (I've had no problem identifying all the other connections). The instructions suggest that it should be in the left hand compartment where the cd changer sits, but I've searched that thoroughly and there's no loom plug there. Nothing in the spare wheel area either. I haven't removed the boot LH side panel yet (forward of the cd cubby over the wheel arch). I can see the earth point I'm supposed to use behind it when I look into the cd changer cubby. Is the plug behind that panel?

If anyone can give me a steer I'd be grateful. The original westfalia kit just plugged right in so the extension should be the same. There must be a loom plug somewhere.

Thanks

Simon

[X5Sport]

The problem was that BMW didn’t fit those wires either. As the option wasn’t used in Germany they didn’t bother for any market. I had to get mine fixed under warranty in both the X5 and X6 with factory tow bars. The brochure said 13-pin wiring so it needed to be complete, not minus a key connection for the fridge! All I know is they went and added more wires but not if they actually plugged in. I was given the impression that they tapped off a circuit at the battery and added a separate fuse.

However, this thread may help…..but the member hasn’t been seen since 2017.

viewtopic.php?t=2357

[SimonS]

Thanks.

I checked the trailer socket connector in the boot. Only 10 cables on both the car side and the socket side. I presume the two missing wires are the fridge power and earth. So it appears that you are right when you suggest nothing exists wiring wise in the car. Or even out to the socket that came with the Wesfalia wiring kit. So the extension I've been sold is a wild goose chase. I suppose I can use it with a few alterations but it would have been good to know that from the start!

Thanks for the advice it was useful.

[Alan Gunn]

Can you sent id back.
A relay and a bit of wire is all you need and i mean a bit as the battery is in the boot.
Not done one for 20 years but was easy from memory but that is not so good today lol.

[gmc15]

Simon, I know this doesn't solve your problem, but do you really need the fridge to work while towing? None of my BMW's have had the wiring for the fridge and I have learned to manage without it. The fridge in the caravan needs to be cold before setting off and the car will only try to maintain the temp. It will not cool a fridge from ambient when towing.
We pack any fridge items in a cool bag with ice packs and put it in the car and everything stays cold until we get the van on site and fridge plugged into the mains.
If the fridge is cold and you are travelling home/elsewhere just freeze a couple of bottles of water the day before and put them in the fridge and it will help keep it cool.

HTH

[SimonS]

Gmc15 The honest answer is it's a nice to have rather than essential. Most of the time on a short hop its unnoticable, but there were a couple of occasions in Spain on the last trip when the interior of the fridge got overly warm. Having installed the westfalia towbar kit I thought it would be a similarly easy experience. Just plug in the extension and away we go. However now I've emptied the boot, got all the panels out and exposed the battery, I've decided I might as well finish the job. Alan yes I could have tried to send it back, but since it has the relay, fuse and correct diameter cables for the sake of getting it done without more trips into town or waiting for stuff from Ebay I'm just going to cannibalise it. The instructions actually wanted me to lead the cable up to the engine compartment to pick up a permanent/switched live when they are easy to find in the rear compartment. One of the unused relay slots is energised by terminal 15, and I'm hoping to pick up terminal 30 there as well rather than leading a cable to the battery. This evening I threaded a couple of cables down to pin 10 and 11 in the socket so I should have it done bytomorrow and be able to get on to doing something more interesting.

Thanks all.

[Alan Gunn]

I think it is telling you to run a wire from the front as the battery is more often there.
Amazon prime for me with bit's like that can always send back what i don't need lol.

[SimonS]

Just to close this thread, here's what I did.

Run 2 x 2.5 mm sq cables down to the socket. Yellow and black in the photo. I slit the sleeve to create entry and exit points.

PXL_20240906_153859460.jpg (153.68 KiB) Viewed 2371 times

In the spare wheel well lead the earth to the left and connect to the earth point. Lead the supply cable to the right and up into the fuse box cubby.

PXL_20240906_141651563.jpg (186.33 KiB) Viewed 2371 times

Up in the fuse box use the vacant left hand relay slot to access both the permanent live and switched live terminals to energise the fridge relay. The orange goes to switched live and yellow to permanent live. The brown wire is the relay coil earth which is connected to an earth point just behind the relay that you can't see.

PXL_20240906_153524287.jpg (169.89 KiB) Viewed 2371 times

Finally the swithed live is already fused by fuse 80. Swap the 20A fuse for a 15A. The pic shows the location of fuse 80

PXL_20240906_153541258.jpg (175.71 KiB) Viewed 2371 times

It is better not to buy the extension kit as you only need the relay plus relay plug, 2m and 1m of 2.5mm sq cable (different colours) and some blue crimp connectors.

[X5Sport]

Glad you got there, and thank you for the information and pictures of your solution.

[Alan Gunn]

Glad you got it sorted out.
A garage i worked in always gave me that job just because i was into radio (Ham) so they thought i was good with electrics.