GMC 2003 Sierra - Manual (Page 372)

II ycjuf vehicle Is eQulpped with the “Heavy-Duty
Trailering" option, please refer
\a Hesvy-Duiy Trailer
W ipng Package, earlier in this sect ion ^
When the cam per’wiring harness is ordered without the
heavy-duly irailering package, an eight-wire harness
with a seven-pin connector and separate CHMSL
connector are locaierf at the rear of the vehicle and are
tied to ihe vehicle's Irame.
Auxiliary Battery
The auxiliary banery provision can ba used to supply
eledtricat power to additional aquipmenl that you
may choose to add, such as a stide-in camper.
II your vehicle has this
provision^ this relay will be
located on the passenger's
side of the vehicle, nent
to the auxiliary battery.
When using this provision, connection should Oinly be
made to the upper stud (A) ot the relay, Do not
make connections to thg tower stud {B) of the relay,
The auxiliary battery cirtuil le protected by a mogaiuse
located bshind the auxitiary battery.
Be sore to follow the proper inslaHation instructions that
are included with any etectrical equipment that you install.
Notice: When using the auxiliary battery provision,
the electrical load must nol exceed 30 amps.
Always turn off any electrical equipment when not
En use. Leaving electriOBl ectuipmcnt on tor extended
periods will drain your battery.
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