Hi All,

Bit of a strange one this. Just got a replacement caravan (yes, sorry about that), but the towing lights don't work properly when connected to the Range Rover. Indicators and random other lights don't function and the car doesn't seem to detect that it has a trailer connected. They are 13 pin electrics.

The caravan has been tested via a test box and on another car and checks out fine.
The Range Rover has been checked at a local Indy and is apparently fine.

The lights worked fine on our previous caravan (although that had LED rear lights) and they're working fine on a 7 pin trailer board via an adaptor.

The lights on the caravan are all bulbs and the Range Rover is LED (2010 facelift).

I'm a bit stuck about how best to proceed to sort this out. Anyone got any ideas? 2010 4.4 TDV8 Vogue SE

The car may not have been told that it's got 13 pin electrics in the ccf, I know you said it worked before you just might have got away with it.

That's the only thing I can think of. 2017 SDV8 4.4 silicon silver AB
2012 TDV8 4.4 Stornaway Grey AB
2011 TDV8 4.4 Buckingham Blue
2012 VW V6 3.0 Tougreg

Hi,

Thanks for that. I did set it all up when it was installed. Enabled tow assist and everything.

It worked perfectly on the previous one which had led lights. 2010 4.4 TDV8 Vogue SE

Hi,
I had similar problem with our caravan, which did have LED lights.
It is a swift. Sargent Electrical, who do most of the swift electrics, do some conversion kits that you fit to the fuse box inside the caravan. Maybe you need one of these.

But I am surprised you have problems if you have filament bulbs. (Has someone swapped them out for LED bulbs).

https://sargentltd.co.uk/shop/interface

Its the VLM products.
James 2011 Range Rover Autobiography TDV8 Buckingham Blue

Thanks for that. It is a Swift - they seem to be the only ones that suffer from this sort of problem.

I've been looking at the modules but as far as I can tell, they're to correct the problem the other way round - ie filament lights on the car and LEDs on the caravan.
Sargent suggested I install their latest module, but it appears to be completely incompatible with my caravan (it specifically states that it's not compatible with anything made before 2016) and I'm pretty sure it won't solve the problem anyway - It's also very expensive just to try it.

My caravan service place isn't very helpful, but I spoke to another who seemed to know what they were talking about (and are advertising some of the earlier modules from Sargent) and he didn't think it would solve the issue - he re-iterated that they were intended to solve the problem of LED lights on a caravan. There shouldn't be a problem with filament lights.

You've got me wondering now though about the lights - our previous caravan was a much earlier model and that had LED lights. Our servicer thought that this one had had the rear end replaced.
I wonder if they cheekily put filament lights in instead.

But they should still work, surely!!? 2010 4.4 TDV8 Vogue SE

My two theories:

1. Check the terminals at the back of the 13 pin socket on the car are in good order and that there's no loose wires


2. Once checked, the 13 pin has multiple earths. The Range Rovers are sensitive to the various circuit grounds being matched to the relevant ground in a 13 pin plug, becuase it's controlled to the tow ECU, not direct to the battery. A simple example: an accessory wired to the fridge +ve won't function if the GND is connected to the permanent live GND. But if connected to (+ve)fridge and (GND)fridge, it would work. The electrics on the Swift may be using any GND, which the Range Rover is sensitive to. 2015 Range Rover Autobiography 4.4 SDV8

Quick Update.

My caravan service guy had a theory that maybe the pins on the socket might have expanded.

He gave me a replacement socket. Whilst trying to contact clean my socket, I realised that the new socket had noticeably smaller sockets than my existing westfalia one.

I was still a bit dubious but ended up changing the socket.
Tried it today and everything now works!

I'm very surprised that my westfalia socket seemed to be incompatible with this particular plug. Everything else I've tried on it worked OK. The caravan has been tried on 3 other cars and it worked fine on all of them.

Anyway, thanks for the help. 2010 4.4 TDV8 Vogue SE