[AT] OT Electric trailer brakes

Ronald L. Cook rlcook at longlines.com
Tue May 19 06:59:55 PDT 2009


Lew,
	I don't know how your pulling vehicle is wired up, but my problem on 
one vehicle was the vehicle ground.  Corroded.  The lights worked 
apparently because the ground through the ball was sufficient for that, 
but the brakes were a two-wire system as you relate.  The ground went 
from the outlet to the frame and was corroded at the attachment to the 
vehicle frame.  The first clue that something was haywire was the brakes 
operating with the four-way flashers that I applied to signal backing. 
Another vehicle runs both wires up to the engine compartment somewhere 
and gave no problem with the same trailer.  Someone probably did a 
better job of wiring.  I had the problem vehicle wired up at the trailer 
sales place where I bought the trailer.  What a mess!!!  I am not going 
to mention the language spoken by the work force at that place.  I will 
never do any business with them again, though.  The hitch and all wiring 
was a package with the trailer, or I would have done it myself.  I had 
to do it all over anyways, so I did not gain anything except a lightened 
billfold.

Ron Cook
Salix, IA

Lew Best wrote:
> I've seen lotsa grounding problems for sure but don't think that's the case
> here.  The plug uses 2 terminals for hot & ground; 2 wires going to the
> brake coils & each coil has 2 wires.  No grounding thru the frame. Seems to
> be correct voltage to the coils but I'll put an ammeter on each one & in the
> main line checking for 3 amps per coil; 12 amps overall. 
> 
> Lew



More information about the AT mailing list