What is a ModuLite, ModuLite Lite And ModuLite HD?
A ModuLite is a trailer light power supply module which provides
power to the trailer lights directly from the tow vehicle's
battery. By powering the trailer lights in this manner, the tow
vehicle's tail, turn and stop light circuits are not exposed to
any additional loads.
Why Is This Important?
In many cases the tail, turn and stop light circuits of today's
vehicles are connected with light gauge wire, designed only to
carry enough current to supply the lights the vehicle is
equipped with. Additionally, some vehicles are equipped with
sensitive electronic devices, such as "lamp-out" sensors, which
are designed to monitor the vehicle's electrical system and warn
the driver of problems with that system.
The additional load of trailer lights
on these devices can cause them to react falsely and in some
cases may lead to their failure.
Which Vehicles Need A ModuLite?
Is the vehicle equipped with any
option packages that include a lamp-out sensor or other
electronic devices that could be damaged by attaching
trailer lights directly to the vehicle's electrical system?
If so, a ModuLite is required.
Is the trailer being towed
equipped with more that one light assembly per side? Does it
have clearance lights, dual tail, turn or stop lights or any
other equipment that will impose an extra load? If so, a
ModuLite is required.
Is this the only trailer the
driver will ever tow? Consider future requirements as well
as current ones. In future applications, a ModuLite may be
Are There Other Ways To Determine
The Need For A ModuLite?
Yes. Vehicle manufacturers caution consumers against adding
additional loads to electrical circuits. Consult the vehicle
owner's manual when recommending trailer wiring. The following
are two examples from owner's manuals:
Jeep Grand Cherokee
"Do not connect a trailer lighting system directly to the lighting
system of your vehicle. Use an approved trailer wiring harness.
Failure to do so could damage the vehicle electrical system
and/or result in personal injury."
Dodge Ram Pickup
"Towing a trailer equipped with more than the standard lighting
(turn, tail, stop and back-up lamps) may cause an abnormally
high electrical draw through the headlamp switch, causing the
switch to fail."
Does A ModuLite Take The Place Of
A Taillight Convertor?
Yes. ModuLites are designed for use on vehicles that have separate
tail, turn and stop light circuits and converts them to standard
trailer light wiring configuration. ModuLite and ModuLite HD
also feature a hazard flasher override circuit. If the hazard
flashers are engaged and brakes are applied, brake lights will
be shown on the trailer. This is an added safety feature that
most taillight convertors do not provide.
Can I Still Use A ModuLite If I
Don't Need A Convertor?
Yes. They can be used on any vehicle that requires a reduction of
load on its electrical system.
What Other Features Do ModuLites
Because a ModuLite receives its power directly from the tow
vehicle's battery and not the turn signal circuit, the need for
a heavy duty turn signal flasher is eliminated. Their advanced
circuitry provides maximum trailer light brightness.
How Long Does It Take To Install A
Approximately 30 to 45 minutes depending on the difficulty of
running the power supply wire from the battery to the rear of
What Does The Wiring Kit (18151)
Wiring kit 18151 comes with everything needed to install a
ModuLite including 20 ft. of special undercar 12 ga. wire, fuse,
fuse holder and attaching terminals.
ModuLite Do I Need?
To determine which trailer light power module you may need, follow
these basic guidelines. Add the number of amps required on the
trailer you will be towing (see below). If the total is less
than 4 amps per light circuit, ModuLite-Lite is recommended. If
the total is between 4 and 10 amps ModuLite is recommended. If
the total is more than 10 amps, a ModuLite HD is required.
Remember to also consider your future towing needs. While
ModuLite-Lite may be adequate for their current trailer, a
different trailer may have a higher amperage requirement making
ModuLite or ModuLite HD the better choice.
Estimating Trailer Amperage Per