Tow wiring

[Adam Hicklin]

You electrical gurus.....I have an issue.  I took out the 6 pin plug at the back of the coach and replaced with a 7 pin, leaving out the center reverse light wire.  I'm really only interested in turn indicators, stop and running lights for the toad.  Turn indicators work fine, running lights work fine.  Hit the brake and I get nothing, and every pin has 10v on it with brake pedal pressed.  Any ideas?  Brake comes over turn indicator wire.  How can I have turn indicator, but no brake?

[Roy C Tyler]

When I purchased my Monterey in 2013, the dealer had to add a box just before the plug in order to get everything to work right.  We tow a 2001 Honda Accord and I believe the brake lights working on the Honda was the problem they encountered.  Everything works right now but I do notice that the Honda brake lights are a little dim when connected to the MH.  I don't know if this information will help you but I thought I would throw it out there.

[Steve Huber Co-Admin]

Adam,
Couple of questions;
-Year and make/model of toad?
-Did all lights work when using the 6 pin connector?
-Do you have a supplemental braking system installed in the toad?
-Do emergency flashers work when signal supplied from RV?
Steve

[Adam Hicklin]

Adam,
Couple of questions;
-Year and make/model of toad?
-Did all lights work when using the 6 pin connector?
-Do you have a supplemental braking system installed in the toad?
-Do emergency flashers work when signal supplied from RV?
Steve

I think I figured it out.  Actually a local hitch shop figured it out.  Apparently there is a converter box that takes the separate turn indicator and brake circuits and combines them them to one because all trailer plugs combine the turn/brake wire.  They figured that there was a converter somewhere that went bad.  Instead of looking for it, we just added a new one and re-wired the plug.  Now, the only problem is when the running lights are in, nothing else works.  Running lights off, all works as it should.  This is a toad wiring problem because the MH plug worked perfectly at the shop.

Steve, I'm towing a 2002 Silverado
The 6 pin was all jacked up so I never tried it to see if it worked previous.
Flashers work
I ran a completely separate line for the toad lights.  I don't use any wiring or lights original to the toad.
Supplemental braking is an M and G. 

[Steve Huber Co-Admin]

Adam,
Glad you got it figured out. I'm a bit confused though as to how the running lights can affect the toad circuit if you added a completely separate circuit (wiring and bulbs?)  to the toad. Have you checked the voltages present on the plug when running lights are on (BTW are these the RV or toad running lights?).
Steve

[Adam Hicklin]

Steve, I'm confused too.  Makes no sense. The plug on the motor home checks out good in all the different phases- ground, left/right/brake, running lights.  I go in to a four pin round plug on the toad. Ran a four wire from the plug to a terminal strip in the back (driver's side) jumper over to another terminal strip on the passenger side.  Then ran a double filament bulb from each terminal strip up to the lens on each side.  It's super clean and completely bypasses any toad wiring.  I'm trying to get out of here so maybe at the first stop (Zion) I'll have some time to troubleshoot. 

Until then, thanks for the help everybody. 

[Jerry Emert]

Adam, I've got pretty much the same problem.  I tore down the plug on the MH, checked all the wiring going to the 4 pin connector on the MH.  Then I checked all the wiring in the cable between the MH and the Toed.  I have separate trailer lights that I stick (magnetic) to the bumper of my truck.  They still don't work completely.  running lights work, left turn works on turn and hazard.  Right works on brakes.  It's crazy.  I use a Ready Brute Elite so at least I know the brake lights on the truck work when I brake.  I'll start over again next trip.  I hope you find the issue.
Jerry

[Steve Huber Co-Admin]

Adam,
Is it possible that the added bulbs are getting ground through the running lights? That could explain the symptoms. Everything would seem to work until 12v is applied to the running lights which would deprive the other circuits of a ground. This would also explain why the toad lights seem a little dim.
Steve

[Adam Hicklin]

Steve, that could be an explanation.  I'll have to tear in to it when I get back home.  Every RV/trailer light problem I've ever had has had something to do with a bad errant ground.  For now, I'll just drive when it's light out and if I get into a situation where I need to drive at night, I'll unhook and let the wife drive the toad.  I've had the coach for 2.5 years and have never driven at night anyway.

Jerry, if I find the problem, I'll let you know.  You reminded me....I have a set of those portable, magnetic lights.  Maybe I'll plug them in to the MH and see if I experience the same problem.  At least that way I can eliminate the coach.

We're on the road now.  Zion, Yellowstone, maybe Grand Tetons and Park City if we have the time (I still work, dammit)

Bonus:  I saw diesel for $2.69 in Utah.  This trip keeps getting better!

[Bob Jae]

Adam
If you still have not found the converter box that you think is bad I believe you need to find that and get it out of the circuit.  Then make sure your new converter box is hooked up correctly.

[Adam Hicklin]

Bob,

Any idea where it might be?  I've looked all around the back where it should logically be.  May e a call to Ken could be helpful.

[Bob Jae]

Adam
Its hard to say on my friends Holiday Rambler it was a few feet back from the trailer plug but pretty well hidden as it was covered with the black spray they use.  I believe it had 5 wires into it and 4 out or the other way around.

[Edward Buker]

Adam,

If you have simply added new bulbs and sockets and use none of the toad wiring then my guess is you just have a wire crossed or a broken filament that lays across another. I think when your tail light are on they are crossing to the brake lighting side o that you can never get the off condition for the blinker lighting. Check your socket mating to the bulb pins also for possible shorting of contact points. I think this problem has to be on the toad new wiring side if you have probed the motorhome plug and all is well there voltage wise.

Late Ed