Wiring tow lights

[Lin]

I have an old set of magnetic tow lights I want to use for the present.  The harness has four wires.  The existing connector on the bus has four pins.  It seems the harness is wired to have one wire (white) as ground, one each (black and yellow) for each direction, and one more (red) lighting both lights.  Does anyone have a handy diagram of how to connect things.  Currently the bus's four prongs are dedicated to two directionals, tail, and brake.  Wiring the directionals and tail are therefore straight forward, but I am not sure how to do the brake.  If I wire it to both directionals, won't the brake light over ride the blinker if I am braking and turning?  Will some sort of mischievous feedback occur.  I am wondering if the brake should be left off the set up, and I should depend on the bus brake lights alone.  They are certainly high enough to be seen.

I must admit that the bus connector did not have the brake lights wired in.  I added that today before I bothered to look at the tow light harness.  Duh!

[Busted Knuckle]

Lin,
Why not use one of the wires you got in the 4 for the brakes and attach a seperate groud wire to it, most times it will ground thru the hitch. But just to be on the safe side I'd make a ground wire pig tail on both ends and fix a ground to the bus and toad/trailer that could plug in to it! FWIW   BK 

[Dallas]

Lin, Check this thread in the Help files out:

http://www.busconversions.com/bbs/index.php?topic=5097.0

[gumpy]

You don't say what bus you have, but it sounds like an MCI. Of course we've been dealing with this issue for many years.

There was another thread on this subject this week, and have been many others in the past. There's good info there, including
diagrams for converting 24v 4-circuit bus to 12v 3-circuit toad.

http://www.busconversions.com/bbs/index.php?topic=7579.0

craig

[Lin]

BK,
     I think that I am leaning toward running an extra wire.  However, what I may do is mount an additional light on top of each magnetic fixture and run the new wire to them for the brakes.  I think that they will ground by the attachment screw.  Sound reasonable?

[Ednj]

http://www.ontheball.com/taillight_convert.htm

You can get these at Walmart they have instructions.

[Lin]

Ed,
     Thanks for the link.  Do you know if these work with 24 volts?

[Sojourner]

If your bus is 24v and tow is 12v....no because you need an relay system like either Craig's or Jack's.

Go back to gumpy's post and click on it. That link has gumpy and Jack Conrad posts with wiring diagram.

Your needs is to take 24v signal pulse from bus to relay into tow's 12v power signal.

Read the their links and it cover all you need to know....or you can e-mail them.

FWIW

Sojourn for Christ, Jerry

[Lin]

Jerry,

They're just magnetic tow lights.  I have put 24v bulbs in them, but have the issue with the brake light.

[Nick Badame Refrig/ACC]

Hi Lin,

What sup. braking system do you have?

Quote: I am wondering if the brake should be left off the set up, and I should depend on the bus brake lights alone.  They are certainly high enough to be seen.

My Roadmaster sup. brake applies the brake lights on the toad in proportionate. Maybe thats your answer if you don't allready have a sup. brake system. ??

http://www.roadmaster-tow-bars.com/evenbrake.php

Nick-

[Sean]

This circuit will convert separate brake and turn lights into consolidated stop/turn lights.  It will also convert 24v to 12v if you also need that:

[From http://odyssey.smugmug.com/gallery/131040_g58Tf#4750590_JifrZ-O-LB]



Use 24-volt relays if you have a 24-volt coach.  Supply the lights with 24- or 12-volts depending on what bulbs you are using.

HTH.

-Sean
http://ourodyssey.blogspot.com

[Lin]

Nick
     There is no supplementary brake system.  I do not know what, if anything different we will do long term, but we are moving and will pull a Camry on a tow dolly.  I am trying to adapt the magnetic lights I already have.  If I like the tow dolly, since I have never used one before, I may put some brakes on that.  Then again, we may get a vehicle that can be pulled four down.  As of now, I finished mounting an extra light on each of the magnetic lights and ran a separate wire for it to be the brake lights.  It bench-tested fine, but went weird when attached to the bus.  Since I am using the four pin connector that was there when I bought the bus, I will now have to take a closer look at it to determine if it has problems.  Otherwise, it is possible that there is some bleeding back through the bus system and I may need some diodes.   I am not an expert at this, among many other things, so my solution may not be particularly graceful, but right now I just want to get to our new home with all (reasonably) intact.  We have bought a used, 45 foot Fruehauf trailer, are loading it, and paying a trucker to pull it for us.  When there, we will probably keep it to use for storage.  That will free the garage up to be for tinkering. 

Sean
     Thanks for the diagram.  It looks like a clearly superior way to go.  I will probably stick with inferior now.  There is just to much to do before we leave.

[Nick Badame Refrig/ACC]

Hi Lin,

I wish you happiness in your new home. Please be safe as I know you will.

Nick-

[Ednj]

http://www.ontheball.com/taillight_convert.htm

You can get these at Walmart they have instructions.

Ed,
     Thanks for the link.  Do you know if these work with 24 volts?

Yes they work as long as the trailer or magnetic lights are 24 volts.
They come with quick connectors.

[Sam 4106]

Hi Sean,
In studing your relay diagram it appears that the turn signals on the towed vehicle will flash twice as fast as the towing vehicle if the brake lights are on at the same time as the turn signals. It appears that the turn signal relay becomes a flasher too when the turn signal flasher alternately switchs the turn signal relay off and on, thus causing the brake light to also switch off and on. Or, am I overlooking something.
Thanks, Sam 4106