Modern car rear lights!

[bert]

And switch off vehicle rear fog but leave on trailer fog.

[bert]

I sometimes find it difficult with the rear LED indicators placed in the centre of circular rear lights esp when brake lights are also on.

[bert]

In article , "Dave Plowman (News)" writes

If it does sell it to them as a smart meter that works.

[bert]

I know, lets have a little illuminated arm in the side of the vehicle, one on each side which comes out to show which way you have just turned. It should be positioned with in reach of the driver so you can turn round and thump it if it sticks.

[Andy Burns]

I thought the 7 pin sockets had been doing that with an inbuilt switch for decades?

[dennis]

It didn't make fitting a Vauxhall towing kit difficult. The computer now monitors the trailer lights as well as the car lights.

[NY]

The 7-pin (as opposed to 13-pin) socket doesn't have a pin that is dedicated for use by foglights? They have separate pins for left- and right-hand tail lights (why?) but none for fog lights - unless you sacrifice the permanent

12V feed for a fridge. When my parents had a caravan in the early 70s, they had an extra wire for foglights which they had to remember to plug/unplug when they were hitching/unhitching the caravan. While some cars may have once had side/tail lights that could be controlled individually, for use as parking lights, it seems weird to waste a pin replicating that onto the trailer, when it means you can't have both permanent live and fog lights. Mind you, the lack of a reversing light pin is also odd: how else is the car behind supposed to know that you intend to reverse?

[Steve Walker]

But all the cars that I have owned (before the current canbus one) have had separate fuses for left and right tail/sidelights and a single fuse for brakelights. I have always presumed that this is so in the event of a single fuse blowing, you are not left on a country road, in pitch darkness, with no lights at all and liable to be crashed into. Trailer connections merely continue the existing split circuits.

Not at all odd. Many cars (most) would not have had foglights or even reversing lights when the 12N socket first appeared and in all likelihood no trailers or caravans would.

Once the 12S was introduced there was no need for the permanent live in the 12N, as that could be dealt with in the 12S. Both fog and reversing lights could have gone in the 12S, but that would have meant that both sockets would be needed on every towcar, but by putting the foglights onto the 12N, only one socket would be needed for towing basic trailers.

Reversing lights are not a requirement, hence the 12S is not mandatory.

In fact according to the Road Vehicle Lighting Regulations, reversing lamps are optional, even on cars, never mind trailers! You cannot be fined (or fail an MOT) for not having a reversing light or for it not working.

On the other hand, plug a trailer or caravan with reversing lights into a car wired to the old (pre-12S), permanent-live standard and they will be on all the time. And showing a white light to the rear, except when reversing, *IS* an offence.

SteveW

[Graham.]

Precisely what I had in mind.

[Andy Burns]

This was donkeys year ago, with twin 7 pin sockets (one grey, one black)

[NY]

Yes, I was referring to the single 7-pin socket, as opposed to the later twin 7-pin sockets or the even later 13-pin.

Is 13-pin now the standard - do all new trailers/caravans/bike racks now come with a 13-pin plug? When we bought our new car a couple of years ago, we got them to fit a 7-pin socket because our old bike rack had a 7-pin plug. We should have planned ahead and got them to fit a 13-pin socket and buy an adaptor, given that we've since bought a new, better bike rack with a

13-pin plug (and had to buy the converse adaptor).

Going back to the earlier point, were some cars' 7-pin sockets fitted with switch which disabled the car's fog (and maybe reversing) lights when they sensed a plug in the socket? I bet you had to keep the socket clean to avoid that switch getting gunged up.

[Michael Chare]

In the case of my car, quite an expensive option compared to the cost of the parts for a fixed tow bar. I have not had difficulty fitting tow bars to previous vehicles.

[Michael Chare]

It now doubt depends on the vehicle, but in the case of my car, running cables from the back of the car and then connecting to the BCM plugs is about as awkward as it gets. It took some time just to find the plugs as they are out of sight even after the CD player in the glove box and the glove box have been removed.

[Dave Plowman (News)]

Very much depends on the vehicle. Some need different rear suspension too. So a factory fit might cost less than retro.

[Chris J Dixon]

My memory is that they did have such a contact, which was out of sight, and I don't recall any problems with contamination.

Chris

[Steve Walker]

The switches did fail ... frequently.

I am glad to be away from those now - the car recognises a trailer is connected and disables the rear fogslights electronically.

SteveW

[Andy Burns]

The slow boat arrived yesterday, amber LEDs fitted this morning, equally bright as the old bulbs, cheaper than incandescents from halfords, no CANBUS warnings.