Page 45 of 60

Black plate (15,1)Chevrolet Tahoe Police and Special Service Packages - 2012
Special Equipment Options 15-15
Wiring Provisions for
Emergency Vehicle Roof
Light - SEO TRW
Battery power is supplied through a
30 amp fuse to a wiring harness
located in the roof. Power is
controlled with a switch located in
the overhead console. The
customer or vehicle upfitter must
complete the installation to an
added accessory such as an
emergency beacon lamp.
Maximum rated electrical load is
21 amps (250 watts). The added
electrical requirements must not
exceed 21 amps (250 watts).
Running the accessory for long
periods of time with the engine off
may run the battery down.Installation
Instructions
–Emergency
Vehicle Roof Panel Lamp
Wiring to the accessory can be
done by either directly connecting
the wire in the roof to the accessory
(Option A) or by using Wiring
Harness Package part number
12150250 obtained from GM
Service Parts (Option B).
A. 645 mm (25.39 in)
B. 440 mm (17.32 in)
C. 100 mm (3.94 in) square D. Roof Centerline
E. Roof Edge
1. Disconnect the negative (−)
battery cable at the battery.
2. Make the electrical connections using either option A or option B.
Notice: Pulling the wiring
harness through a panel hole that
has sharp edges may cause
damage to the wire and/or wire
insulation. Remove sharp edges
from the panel hole before pulling
the wire through it.
Option A: Roof Wires Directly to
Accessory
1. Drill a 10 to 13 mm (3/8 in to 1/2 in) hole in the outer roof
panel in the area shown in the
illustration. The hole should only
go through the outer panel.
Remove all sharp edges from
the drilled hole.
2. Remove the inside overhead console access panel/lamp
lenses.
Page 46 of 60

Black plate (16,1)Chevrolet Tahoe Police and Special Service Packages - 2012
15-16 Special Equipment Options
3. The accessory harness is coiltied to the passenger side of the
vehicle at the console inner
bracket.
4. Cut the tape holding the harness coil.
5. As one person watches the roof hole from the outside for the end
of the harness, a second person
from the inside of the vehicle
should snake the harness
toward the hole.
6. Pull out the wiring harness being careful to avoid scraping the
insulation on the edge of
the hole.
7. Extend the wiring harness to the accessory. 8. Connect the dark green wire to
the accessory hot terminal.
9. Connect the black wire to the accessory ground terminal.
10. Cover the hole in the roof with a durable sealant such as
silicone rubber sealer.
11. Reinstall the overhead console access panel/lamp lenses.
Option B: Use Wiring Harness
Package 12150250. Obtain from
GM Service Parts through the GM
Dealership
1. Drill a 32 mm (1.25 in) hole in the outer roof panel in the area
shown in the illustration. The
hole should only go through the
outer panel. Remove all sharp
edges from the drilled hole.
2. Remove the inside overhead console access panel/lamp
lenses. 3. The accessory harness is coil
tied to the passenger side of the
vehicle at the console inner
bracket.
4. Cut the tape holding the harness coil.
5. As one person watches the roof hole from the outside for the end
of the harness, a second person
from the inside of the vehicle
should snake the harness
toward the hole.
6. Pull out the wiring harness being careful to avoid scraping the
insulation on the edge of
the hole.
7. Cut the wire to length. Install terminals to wire ends and insert
into the connector. The dark
green wire goes to cavity A and
the black wire in cavity B. Push
in the secondary lock to retain
the wires.
Page 47 of 60

Black plate (17,1)Chevrolet Tahoe Police and Special Service Packages - 2012
Special Equipment Options 15-17
8. Attach the harness assemblyfrom the package to the
accessory. Cover with the
supplied conduit for added
protection. Connect the orange
wire to the accessory hot
terminal and the black wire to
the ground.
9. Complete the connection from the roof harness to the extension
harness. Cover the mated
connector with the supplied
foam. Push the foam covered
connection and excess wire
through the roof panel hole.
10. Reinstall the overhead console access panel/lamp lenses. Restoring Power
The auxiliary lamp switch is located
on the overhead console.
This switch includes wiring
provisions for a dealer or a qualified
service center to install an auxiliary
roof lamp. When the wiring is
connected to an auxiliary roof
mounted lamp, pressing the bottom
of the switch will activate the lamp and illuminate an indicator light at
the bottom of the switch. Pressing
the top of the switch again will turn
off the roof mounted lamp and
indicator.
1. Be sure that the auxiliary lamp
switch is off.
2. Vacate the vehicle and reconnect the battery cable.
3. Turn the auxiliary lamp switch on. The accessory should now
be working. If it is not working,
check the connections.
4. After ensuring that the accessory is working properly,
install the grommet in the hole.
Seal with silicone sealer to
prevent water leakage.
Notice: Overloading the vehicle's
electrical system may damage
your vehicle's accessories. Do
not overload the vehicle's system
by having unnecessary
accessories on at the same time.
Page 49 of 60
Black plate (19,1)Chevrolet Tahoe Police and Special Service Packages - 2012
Special Equipment Options 15-19
Wiring Diagram for SEO TRW
Page 50 of 60
Black plate (20,1)Chevrolet Tahoe Police and Special Service Packages - 2012
15-20 Special Equipment Options
Maintenance
The emergency roof light circuit is
fed from the fuse labeled Sunroof
located in the underhood electrical
center. Always replace the fuse with
a 30 amp mini-fuse.
Wiring Provisions
for Horn/Siren
Circuit - SEO 6J4
This provision permits customer
connection of a switch to select
either horn or siren operation when
the horn pad is pressed.A 0.35 mm² (22 gauge) wire is
connected to an in-line connector in
the horn circuit of the instrument
panel harness under the instrument
panel. The end of this harness
extension is in a 1.5 m (5 ft) loop of
wire coiled under the center of the
instrument panel.
Page 51 of 60
Black plate (21,1)Chevrolet Tahoe Police and Special Service Packages - 2012
Special Equipment Options 15-21
Wiring Diagram for SEO 6J4 Inline Connector
Page 52 of 60

Black plate (22,1)Chevrolet Tahoe Police and Special Service Packages - 2012
15-22 Special Equipment Options
Wiring Provisions for
Vehicle Grille Lamps,
Flasher, and Speaker/
Siren - SEO 6J3
Alternating Signal Flasher
A. Blunt cut ends for the Customer-Furnished Grille
Lamps and Customer-Furnished
Siren/Speaker
B. Control Wires from In-Line Connector in Forward Lamp
Harness for
Customer-Furnished Grille
Lamps and Speaker The SEO 6J3 wiring provision option
consists of a 1.5 m (5 ft) wiring
harness coiled underneath the
instrument panel on the passenger
side. The wiring circuits are routed
from underneath the instrument
panel to a 30 cm (1 ft) coil secured
in the area behind the grille. There
are four 1.0 mm² (16 gauge) wires
for connecting to the grille lights
(GRY, TAN) and siren speaker
(LT BU, LT GN)
The SEO 6J3 wiring provision also
includes one 0.8 mm² (18 gauge)
control wire for the SEO 6J7 exterior
lamps emergency flashing system.
When option SEO 6J7 is installed
without option SEO 6J3, only the
dark green/red control wire is
provided for connection to
customer-furnished 12-volt
switching to turn the emergency
flashing system on or off.
Page 53 of 60
Black plate (23,1)Chevrolet Tahoe Police and Special Service Packages - 2012
Special Equipment Options 15-23
Wiring Diagram for SEO 6J3 and SEO 6J7