Blue Ox 2013 Dinghy Towing Guide - Manual (Page 24)

T
he research has been done, the
fi nancing arranged, the papers signed
… and that new dinghy vehicle is now
sitting in your driveway. You’ve shopped
carefully to pick a model that’s certifi ed by its
manufacturer for fl at towing, you’ve checked
the vehicle’s weight to confi rm that it’s within
the motorhome’s safe towing capabilities and
you’ve ordered it with any requisite factory op-
tions to make it towable with all wheels rolling.
Now what?
As any seasoned motorhome owner will
tell you, there are a lot of steps involved in get-
ting a new vehicle to the point where it can be
towed safely. Unfortunately, no automaker
offers a plug-and-play solution that makes its
products ready for safe dinghy towing right
from the factory. Thus, it’s up to you (and
perhaps a knowledgeable towing equipment
dealer) to get the job done right.
DINGHY WIRING
One of the most important aspects of dinghy
prep involves connecting the wiring between
the two vehicles. Tail, brake and turn signals
on the back of the dinghy are required in all
50 states and all Canadian provinces, so this
isn’t a step that you can overlook. (Neither side
clearance nor backup lights are required, and
are rarely used.)
The most common source of dinghy wiring
confusion centers on differences in the way
the turn-signal lights are wired on various cars
and motorhomes. Some models are wired to
supply turn-signal power to the same bulbs
that are used for the brakelights (commonly
referred to as a 4-wire system), while others
use separate amber bulbs for the rear turn
signals (a 5-wire system). Note that 4- and
5-wire systems are used on both motorhomes
and cars, so any one of four solutions may
be needed for any particular application.
Adapters are readily available to electronically
match the wiring systems of the dinghy and
motorhome.
The traditional method of wiring a dinghy
vehicle involves the use of steering diodes,
which function as one-way gates to the fl ow
of electricity, allowing power from either the
motorhome or vehicle to be supplied to the
rear bulbs. Because no electricity can fl ow
backward through a diode, it also prevents
power from the motorhome from being inad-
vertently introduced to any other circuits in the
dinghy vehicle.
Many late-model vehicles are equipped
with on-board diagnostics that continuously
check for proper operation of turn-signal and
brakelight bulbs. Unfortunately, the introduc-
tion of aftermarket steering diodes into the
vehicle’s wiring can “fool” this diagnostic
function, typically causing it to give false warn-
ings about burned-out bulbs.
For this reason, it’s common to modify each
of the vehicle’s tail-lamp assemblies to accept
a separate bulb. This bulb is then connected
Left: One-way diodes, such as this one from Roadmaster, prevent
electrical feedback when using the dinghy’s lighting circuit.
Right: As an alternative, you can install an extra pair of lamps
on your dinghy independent of its electrical system.
Towing Accessories
directly to the motorhome, eliminating any
connections to the vehicle’s existing wiring
harness. This modifi cation usually involves
drilling a large hole in the tail-lamp refl ector.
Fortunately, special snap-in sockets are avail-
able that make this job somewhat easier. Since
the new socket takes up considerable space
behind the lamp assembly, care must be taken
in selecting a location for the new hole that
avoids socket interference with any other ob-
jects behind it.
Note that most states allow the turn signals
to be either red or amber in color, but only
permit the brakelights to be red. Thus, on au-
tomobiles equipped with amber turn signals,
the new socket is typically installed behind the
red brake-lamp lens.
In situations where modifi cations to the
dinghy’s original wiring either aren’t desirable
or practical, a set of removable towing lights
often provides a workable solution. Most
of these products are affi xed with magnets,
although some models can be equipped with
suction cups or hook-and-loop fasteners (ideal
for use on plastic or fi berglass surfaces). A
cable is then snaked across the vehicle to the
connector at the motorhome hitch receiver.
In some cases, the cable is semipermanently
routed inside or underneath the vehicle, allow-
ing the lights to be quickly removed and stowed
inside the trunk. Several companies offer wire-
less, removable towing lights, thereby eliminat-
ing the need for this cable altogether.
Although many motorhomes come with
a factory-installed 4- or 5-pin connector,
there are situations where a different connec-
tor is necessary. Some unapproved dinghies
equipped with an automatic transmission must
also be equipped with an electric lube pump,
Hopkins nVision Tire
Pressure Monitoring
System keeps an eye on
motorhome and dinghy tire
air pressure. The wireless
system can be easily trans-
ferred between vehicles
and used in the dinghy
without the motorhome.
Plug receptacles added to the dinghy and coach allow easy hookup of an electrical connector for taillights, turn
signals and the supplemental braking system.
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