VERY mickey mouse way to hook up tail lights.... but it worked !!!

[boogiethecat]

A friend of mine was towing his girlfriend's car today, and couldn't get the lights to work properly.  Her car had separate night, brake, and turn lights; his had brake and turn combined, the wiring was such that he was having one heck of a time figuring out which was which, and when he finally did he realized he was screwed -- since the two systems were different, it wouldn't work anyway as you can't hook a three wire system with integrated turn/brake lights to a two wire system with separate turn signals without some relays etc...  They were in a fair hurry to leave since it was getting on in the day and they had a 10 hour drive ahead of them.

Since the "towd" was much smaller than the towing vehicle, they weren't as concerned with turn signals as the rest of the lights- the tow car's turn lights could easily be seen from the rear. So I offered a very weird solution ( that just left the turn singnals out of the equation), and it worked.

It went like this:

I hooked a diode pointing from every wire on the towing vehicle that would supply brake or night lighting voltage, to a common point ( took three diodes, hooked the anode of all the diodes together) and then hook that point to all of the wires coming from all the toad's brake and night lights, again all hooked together in a big ball.

What happens is that when you turn on the headlights of the towing vehicle, all the toad's rear lights illuminate, somewhat dimly because there's a lot of bulbs on one smallish circuit.  Then when the towing car's brakes are applied, there's suddenly 2 new sources of 12 volts feeding into the mess, and the lights on the towd get lots brighter.

One ball o' wires does the job of separate circuits as far as anyone following is concerned- the lights get brighter when the brakes are on as they should, then go back to dim when just the headlights are on but no brakes.

Wired weird but it got them on the road safely and quickly....

[Busted Knuckle]

Gary, I agree 100% with the "title" & that it worked. But I must ask wouldn't it have been easier to just use a set of "tow lights"? Personally I believe anyone who tows different trailers, cars, etc. should have a set of these for emergencies just in case ! Then if you happen to be somewhere and need to tow a vehicle that's not already wired to match the power unit, you simply plug in & attach the "tow lights" and away you go! They are not very expensive and can be stored in a small space, but yet could save a lot of time and headache in an emergency, such as needing to tow another toad, or trailer, or even the regular one if it were to have wiring problems. FWIW BK 

[Jeremy]

I must say I thought exactly the same thing when I read the post - it would have been the obvious solution, so I assume that the tow vehicle must not have had a socket for the trailer board (although quite why I couldn't work out, since it is illegal to tow anything without lights, and no matter how the trailer lights are rigged, the tow vehicle needs a socket for them to plug into).

A 'trailer board' or 'light board' as they are called here can be bought for less than £10 (approx $16), which is way cheaper than the component costs of buying the cable etc seperately, never mind the time spent sorting out any other solution.

Jeremy

[boogiethecat]

Yeah guys, that is the obvious solution, to get some magnetic lights etc.... until you remember this was Sunday after 5pm with the nearest car parts store that would even be opened being an hour away in the wrong direction and they needed to get on the road.  Sometimes timing is everything...

The reason for my post wasn't to catch flack over how it should have been done in different circumstances...I totally agree with both of you- instead it was to show you an interesting albeit unorthodox way to think "outside the box" and make things work in a pinch, when the obvious/best  solution is not easly avaliable...

[DrivingMissLazy]

Kudo's Gary. An elegant solution to a solve an emergency problem on a one time basis.
Jeremy, even if there was a trailer connector to plug into, there is always a gender problem, ie 7 pin or six pin versus four pin, and the the incompatibility of generally foreign automobiles wired different than American autos. Bk's solution is a permenant solution, not an emergency solution.
Thanks for sharing Gary. Great idea.
Richard

Yeah guys, that is the obvious solution, to get some magnetic lights etc.... until you remember this was Sunday after 5pm with the nearest car parts store that would even be opened being an hour away in the wrong direction and they needed to get on the road.  Sometimes timing is everything...

The reason for my post wasn't to catch flack over how it should have been done in different circumstances...I totally agree with both of you- instead it was to show you an interesting albeit unorthodox way to think "outside the box" and make things work in a pinch, when the obvious/best  solution is not easly avaliable...

[gumpy]

I don't know why he didn't just hook the brake/turn from the tow vehicle up to the brake light on the towed. Just because the towed has
separate brake and turn lights doesn't mean you have to use them. If you hook the tow vehicle combined signal up to just the brake light on
the towed, it works just fine.

[DrivingMissLazy]

As the old saying goes "more than one way to skin a cat" eh?
Richard

I don't know why he didn't just hook the brake/turn from the tow vehicle up to the brake light on the towed. Just because the towed has
separate brake and turn lights doesn't mean you have to use them. If you hook the tow vehicle combined signal up to just the brake light on
the towed, it works just fine.

[Jeremy]

"Jeremy, even if there was a trailer connector to plug into, there is always a gender problem, ie 7 pin or six pin versus four pin, and the the incompatibility of generally foreign automobiles wired different than American autos."

Interesting - over here there is only one sort of plug, which is a 7-pin. Any differences with how the lights on the towing vehicle is wired are accounted for when the socket is installed, so the output of the socket itself is universal - ie. any trailer or trailer board can be plugged into any tow vehicle.

It is actually very common to have two 7-pin sockets installed on your car in the UK - the first one is the standard one for the trailer lights, whilst the second one is used with caravans to supply power to the fridge, charge the caravan battery etc whilst driving.

Jeremy

[FloridaCliff]

Gary,

Thanks for another helpful Idea that may help someone in a pinch.

Cliff

[DrivingMissLazy]

And to make it even more confusing, there is the 12 or 24 volt issue, electric braking for the trailer and DC power for battery charging or other DC requirements in the trailer or auto being towed.
Richard

"Jeremy, even if there was a trailer connector to plug into, there is always a gender problem, ie 7 pin or six pin versus four pin, and the the incompatibility of generally foreign automobiles wired different than American autos."

Interesting - over here there is only one sort of plug, which is a 7-pin. Any differences with how the lights on the towing vehicle is wired are accounted for when the socket is installed, so the output of the socket itself is universal - ie. any trailer or trailer board can be plugged into any tow vehicle.

It is actually very common to have two 7-pin sockets installed on your car in the UK - the first one is the standard one for the trailer lights, whilst the second one is used with caravans to supply power to the fridge, charge the caravan battery etc whilst driving.

Jeremy

[Busted Knuckle]

Yeah guys, that is the obvious solution, to get some magnetic lights etc.... until you remember this was Sunday after 5pm with the nearest car parts store that would even be opened being an hour away in the wrong direction and they needed to get on the road.  Sometimes timing is everything...

The reason for my post wasn't to catch flack over how it should have been done in different circumstances...I totally agree with both of you- instead it was to show you an interesting albeit unorthodox way to think "outside the box" and make things work in a pinch, when the obvious/best  solution is not easly avaliable...

Gary I'm sorry I wasn't try'n to give you flak. I was merely try'n to offer a simpler idea. I thought Walmart was in every part of the counrty by now (and others too!) I'm sorry if it sounded like I was knocking your solution, I wasn't meaning too. I just thought a quick trip to Wally World, slip in the appropriate 24V bulb hook up & roll with it baby! BK 

[Dallas]

Gary,

Sounds like a very McGyverish solution, and I like McGyver! But hey, I also like Rube Goldberg!

Sounds like a working option and that's all that counts!

Dallas

[DrivingMissLazy]

Jeremy, just thought of another oddity. There is both a 7 pin round and a 7 pin flat connector. LOL
Richard

"Jeremy, even if there was a trailer connector to plug into, there is always a gender problem, ie 7 pin or six pin versus four pin, and the the incompatibility of generally foreign automobiles wired different than American autos."

Interesting - over here there is only one sort of plug, which is a 7-pin. Any differences with how the lights on the towing vehicle is wired are accounted for when the socket is installed, so the output of the socket itself is universal - ie. any trailer or trailer board can be plugged into any tow vehicle.

It is actually very common to have two 7-pin sockets installed on your car in the UK - the first one is the standard one for the trailer lights, whilst the second one is used with caravans to supply power to the fridge, charge the caravan battery etc whilst driving.

Jeremy

[boogiethecat]

Gotcha B.K. !! Thanks for the clarification!!
The reason for the diodes was if I'd have just hooked all the brake lights up, the turn signals on the towing vehicle would have stopped working, 'cause of the combined brake/turn system on the tow and the individual brake/turn system on the toad.  The diodes kept the turn signals on the Tow working fine.

Cheerio!
G

[Jeremy]

"Jeremy, just thought of another oddity. There is both a 7 pin round and a 7 pin flat connector. LOL
Richard"


It really sounds like you lot need to adopt the UK system - just like you already have with so much else!

Jeremy