Trailer brakes
When towing a trailer load of 3,500 lbs.
(1587 kg) or more, trailers with a brake
system MUST be used.
However, most states
require a separate braking system on trailers with
a loaded weight above a specific amount. Make
sure the trailer meets the local regulations and
the regulations where you plan to tow.
Several types of braking systems are available.
Surge Brakes -
The surge brake actuator is
mounted on the trailer tongue with a hydraulic line
running to each trailer wheel. Surge brakes are
activated by the trailer pushing against the hitch
ball when the tow vehicle is braking. Hydraulic
surge brakes are common on rental trailers and
some boat trailers. In this type of system, there is
no hydraulic or electric connection for brake op-
eration between the tow vehicle and the trailer.
Electric Trailer Brakes -
Electric braking sys-
tems are activated by an electronic signal sent
from a trailer brake controller (special brake-
sensing module). If electric trailer brakes are
used, see
9
Electric trailer brake controller
9
in this
section.
Have a professional supplier of towing equip-
ment make sure the trailer brakes are properly
installed and demonstrate proper brake function
testing.
WARNING
Never connect a trailer brake system di-
rectly to the vehicle brake system.
Electric trailer brake controller
Trailers equipped with electric brakes may re-
quire the installation of an aftermarket trailer
brake controller.
Your vehicle is equipped with a connector and
jumper harness that is specifically designed to be
used when installing an aftermarket brake con-
troller.
example
LTI0117
Technical and consumer information
9-23
Z
REVIEW COPY—
2009 Infiniti QX56 (iwz)
Owners Manual—USA_English (nna)
02/29/08—tbrooks
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