T6 trailer lights not working. Where's the fuse?

Hi,
I have a 2018 T6 which has been converted. I cannot get the rear bike rack lights to work. The bike rack works fine on VW golf.

I am trying to find the fuse, I read that's it's under the passenger seat but under the passenger seat we have a safe and then there are these wires (in photos). Can anyone give me some indication as to what these are or do?

I think that the fuse could also be in the bonnet. Would anybody know which one?

I have called loads of different professionals and nobody seems to want to touch someone else's electrics. So if I can't work it out I have to spend £500 on a replacement.

Any help or advice would be greatly appreciated! Thanks

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Depends upon whether it’s a bypass relay, aftermarket dedicated loom or OEM. Relay will possibly be behind a light cluster, aftermarket is usually a few fuses by the starter battery and OEM is under the passenger seat. Also take the rear socket apart and make sure all the connections are sound and clean.
 
Thank you! So the pic in my post I gather is nothing to do with fuses then? Assuming fuse box has potentially been removed and rewired so the fuse must be in the Bonnet somewhere.
 
Originally those couplers would have been held in a plastic frame attached to the seat base, along with any fuses. Check they haven’t been tucked under the carpet.
 
Would have originally looked like this

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Can you post a photo of your build sticker that’s stuck to the underside of the drivers footwell
 
It looks like this

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I can see the code 1D0 which means you don’t have an OEM loom so it’s either a bypass relay or aftermarket do you have a reverse cam or parking sensors? Can you see an image of a trailer overlaid on the screen when selecting reverse with the bike rack plugged in?
 
No the van does not pick up that there is a bike rack on. So when you put it into reverse the reverse sensors go off straight away.

All fuses by the battery seem to not be blown so do not think it is that. What did you mean when you mentioned light clusters?

Thanks
 
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Please post a pic of the fuses by the battery
 
No not there. If you have an aftermarket vehicle specific dedicated tow bar loom then there should be 3 fuses in their own fuse holder connected to the starter battery +ve. If you don’t have this then you probably have a bypass relay that will be spliced to the lighting wiring loom in the back of the van. You’ll need to remove the side ply panels and take a look
 
It will be something similar to this

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Okay thanks for all your help. Connected to the positive terminal as pictured is one 15 amp fuse and the wire goes behind the battery into the van. Any ideas if that would be sufficient?

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Maybe, is it blown? Think your going to have to trace the wiring. Start at the tow socket and see where loom goes into the van, then remove the internal rear quarter panel on that side and investigate further.
 
No fuse isn't blown. Thanks for your advice. I am going to take the plug apart and clean it up and see if that helps. If not I will do some further investigation into the wiring. Thank you
 
So ended up fitting new plug with no luck! May be a stupid question but should the van pick up the bike rack automatically? Or should I tell it that a bike rack is on It. First time using this

Is there any switches or anything that I need to do in the van once the bike rack is on?

I know it worked last November so wondering if there is something small I am missing! Thanks!
 
All depends on what you have fitted and how they do trailer detection.

The simplest have a micro switch in the trailer socket, more common these days is to detect lighting circuits.

For instance my OE towbar needs to find 2 of the following 4 lighting circuits working: Left Turn, Right Turn, Left Side, Right Side

The lighting detection ones can often have issues with LED lighting as there may not be enough of the test current passed through and LED lamp for it to work.
 
Sorry, picking up on something that I saw in your (@Harrisonmurphy16@hotmail. ) photo of the battery, there should not be any wires connected directly to the negative terminal of the battery as that bypasses the battery monitoring module. See red arrow in this photo...

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All negative connections should go to the vehicle metalwork preferably via proper earthing terminals.
 
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