First post and trailer light question...

[bevans6]

Howdy all!  I am getting a 1980 MCI MC-5C conversion in a week or two, and I have a question about trailer lights and brakes.  I'd like to know the best way to convert the 24 volt signals to 12 volt, and the best way to power the brake controller (Tekonsha Prodigy).

I've read that splitting the chassis batteries for 12 volt can be bad if the 12 load unbalances the batteries, but I don't think that trailer lights are all that big a deal.  I can always convert to LED trailer lights, but need 12 volt for the brakes for sure.  I was thinking relay panel for the lights and signals, etc.  Anyone done this, anyone know of an off-the-shelf solution?

Brian

[FloridaCliff]

Brian,

I did the relay setup.

I ran 12Vdc to an electrical bus and then fed the relays, used the existing 24vdc for the rear lights, stop, marker etc to control the relays.

Somewhere in the archives/search is a drawing of the relay setup.

Cliff

[busshawg]

The best way is to go to Gumpy's web site, and click on the link that says you are intersted in buying a converter. Mail him the bucks and he'll send you one with full instructions. MY opinion is that these units have so much work to do to them that one should take advantage of these oportunities. He does quality work. He also has all the info there if you want to make your own.


http://www.gumpydog.com/bus/MC9_WIP/Electrical/Tail_Light_Converter/tail_light_converter.htm


Grant

[belfert]

I assume your MC5C does not have a Vanner for 12 volts on the chassis electrical.

My suggestion to get the 12 volts for the trailer circuit would be to tap off of your house electrical system.  Presumably you will have 12 volts available from your house electrical.  The load from a few trailer lights should not even be noticeable.

I've been lucky as my bus is much newer and they used all 12 volt lights on the exterior plus I have a Vanner for both 12 and 24 volts from the chassis electrical system.  I was able to just use a Drawtite converter for my trailer lighting.

[busshawg]

How rude of me, WELCOME TO THE MADNESS!!  Great bunch here.

Grant

[oldmansax]

Hello Brian and welcome!

I can vouch for Gumpy's converter. I bought one for my MC7 & it works like a charm. I pulled the 12V supply from my house batteries.

Have fun!

TOM

[Hartley]

If you are going to use electric brakes .....

Don't forget the extra wires needed for the 12 volts that feeds the trailer brake controller and the
extra relay (24 volt) to activate it that hooks to the brake light circuit. (up front!)

You have to tap into the brake light circuit and add a relay to switch 12 volts on and off when you use the brakes to tell the controller to activate. Then the BLUE wire runs all the way back to the trailer
connector for the brake circuit.

Most trailer brakes are 12 volts only...

Dave....

[Chopper Scott]

I built a relay system to engage my trailer lights as has been stated previously and added a 12 volt alternator off the engine to keep the house batteries charged also when rolling down the road. Welcome to bus heaven. Later