relay CHEVROLET TAHOE 2012 3.G Owners Manual
[x] Cancel search | Manufacturer: CHEVROLET, Model Year: 2012, Model line: TAHOE, Model: CHEVROLET TAHOE 2012 3.GPages: 60, PDF Size: 1.12 MB
Page 35 of 60
Black plate (5,1)Chevrolet Tahoe Police and Special Service Packages - 2012
Special Equipment Options 15-5
The vehicle is equipped with wiring
provisions for a 12-volt battery
power supply. Refer to the following
information when adding electrical
accessories that will use the 12-volt
power supply feeds connected to
the vehicle's electrical system. The
wiring harness is located below the
instrument panel near the center of
the vehicle. The following
information describes the breaker
and relay location and provides a
wiring diagram to aid in connecting
customer equipment.
Electrical Connections
Notice:Before modifying or
adding any wiring, be sure that it
will work properly with your
vehicle's wiring system. Because
there are so many modifications
that can be made for many
different bodies and accessories,
GM cannot take responsibility for
any changes made. Such
changes may not be covered by
your GM Warranty. Have the work
done by an experienced electrical
technician. All wiring must be properly
protected by fuses, etc. and must
be routed properly so that it will
not be cut, pinched or rubbed by
other parts of the vehicle. Do not
route wiring in areas where it will
be very hot. Be sure not to
overload the vehicle's wiring,
connectors and components. All
added wire must be at least the
same size as the wire being
attached to for proper fuse
protection.
Installation Instructions
–12‐Volt
Accessory Power Supply
1. Disconnect the negative (−)
battery cable at the battery. The
negative (−) battery cable must
be disconnected before the
positive wiring lead is connected
to the power accessory.
2. Locate the power supply harnesses, one under the
instrument panel near the center
of the vehicle, and one within the
driver side rear cargo area jack
stowage compartment. 3. Prepare the wires that are to be
used to connect the power
accessory. Do not remove the
unused wires. Tape unused
wires back in their original
position under the instrument
panel.
4. Complete the wiring installation of the customer added
accessory with additional wire
required for the specific
electrical accessory power
connection. The wire gauge,
3.0 mm² (12 gauge), should be
the same as the wiring of the
installed harness.
5. The ignition must be turned to OFF prior to attaching the cables
to the battery, or serious damage
to the Body Control Module
(BCM) may result.
The windshield wiper switch and
the radio must be turned off
before attaching cables to the
battery.
Page 36 of 60
Black plate (6,1)Chevrolet Tahoe Police and Special Service Packages - 2012
15-6 Special Equipment Options
6. Reconnect the negative (−)battery cable to the battery.
Torque the bolt to 5 Y
(3.6 lb ft).
7. Reset the clock time and radio pushbuttons as desired.
The 12‐volt battery power is
supplied through two underhood
mega fuses, one 125 amp and one
60 amp. This underhood power is
fed to the breaker/relay center via a
harness that passes through the
driver side front of the dash, and
routes across the instrument panel
to a position forward of the glove
box. The breaker/relay center is
mounted to the instrument panel
structure forward of the glove box.
The center includes a plastic
bracket, two relays, two 30 amp
breakers and three 50 amp mega
circuit breakers. Two 30 amp breakers supply power
from the underhood 60 amp mega
fuse through the contacts of the
control relays to 3.0 mm² (12 gauge)
blunt cut wires. These two blunt cut
leads are part of wire coil under the
instrument panel near the center of
the vehicle.
Each relay is operated by a 0.5 mm²
(20 gauge) blunt cut, light or dark
blue control lead included in the
122 cm (4 ft) loop of wire coiled
under the instrument panel.
Three 50 amp mega circuit
breakers, protected by three fusible
links, supply power directly from the
underhood 125 amp mega fuse
through three, 5.0 mm² (10 gauge)
wires. Two of the wires are routed
through the body harness to buss
junction blocks in the left rear of the
cargo area and secured near the
jack and tools. This 122 cm (4 ft) of
coiled wires can be accessed by
removing the cup holder on the top
of the trim panel. The third 5 mm²
(10 gauge) wire is a blunt cut lead
which is part of the 122 cm (4 ft)
loop of wire coiled under the
instrument panel near the center of
the vehicle.
An 8 mm² (8 gauge) ground lead is
also provided, and it is located
under the front passenger sill plate.
It can be accessed by removing the
sill plate and pulling the loop of wire
at the front of the plate. The lead is
122 cm (4 ft) long.
Page 37 of 60
Black plate (7,1)Chevrolet Tahoe Police and Special Service Packages - 2012
Special Equipment Options 15-7
Blunt cut ignition controlled power
and signal circuits are also included
in the wire coiled under the
instrument panel near the center of
the vehicle. They include:
.*A yellow, 0.5 mm² (20 gauge)
circuit, Hot in ACCESSORY,
RUN or RAP (Retained
Accessory Power).
.A pink, 0.5 mm² (20 gauge)
circuit, Hot in START and RUN.
(7A maximum load)
.*A yellow/black, 0.5 mm²
(20 gauge) transmission park
signal. This circuit provides
switched power when the
transmission is in P (Park) and
the engine is running. The circuit
is at 0 volts when the
transmission is in any other
position, i.e., R (Reverse),
N (Neutral), D (Drive) or
M (Manual). Note that the circuit
is also at 12 volts with the
transmission in P (Park) and the
ignition in LOCK/OFF. To avoid
the possibility of undesired
parasitic electrical load with the
ignition in LOCK/OFF it is
suggested that the Park/Signal
circuit be isolated by routing it
through the normally open
contact of a customer furnished
ignition controlled relay.
.A dark green/white, 0.5 mm²
(20 gauge) Vehicle Speed Signal
(VSS) provides 4,000 pulses
per mile.*These two circuits share a 15 amp
fuse. (10 amp combined
maximum load)
Servicing Relays and Fuses
Fuse/Relay Center
Page 38 of 60
Black plate (8,1)Chevrolet Tahoe Police and Special Service Packages - 2012
15-8 Special Equipment Options
Enlarged View of the Fuse Block
A. Relays and Circuit Breakers
B. Front of the Vehicle
C. Floor of the Vehicle
D. Glove Box
E. Tab
The following information tells how
to access the vehicle's relay and
breaker center for checking and
replacing breakers. The breaker and relay center is
located behind and above the
instrument panel storage
compartment. Remove contents
from the storage tray. Using the tab
at the back of the compartment,
drop the tray down gently toward
the floor. It will hang from the hinge.
The breaker/relay center is located
above the right rear corner of the
storage compartment. The bracket
is attached to the instrument panel
structure with two screws.
Replace a 30 amp circuit breaker
with GM Part No. 12182117 circuit
breaker, or equivalent. Replace a
relay with a GM Part No. 12193604
relay, or equivalent. Replace a
50 amp circuit breaker with a GM
Part No. 15319848 circuit breaker,
or equivalent.
Reinstall the storage tray into the
compartment by lifting it into the
instrument panel.
Auxiliary Battery Power
Junction Blocks
Two auxiliary power junction blocks
are located within the driver side
rear cargo area jack stowage
compartment. Each junction block is
powered directly from the battery
through a 50 amp circuit breaker for
connection to customer‐furnished
equipment. The two circuit breakers
are located in the breaker/relay
panel forward of the instrument
panel glove box. A maximum load of
50 amps (600 watts) can be
connected to each junction block.
The wiring diagram for this circuit is
shown as part of the diagram for
“Wiring Provisions
–12 Volt Battery
Power”.