2008 GMC SIERRA relay

Electric Brake Control Wiring
Provisions
These wiring provisions are included with your vehicle
as part of the trailer wiring package. These provisions
are for an electric brake controller. The instrument panel
contains blunt cut wires near the data link connector
for the trailer brake controller. The harness contains the
following wires:
Dark Blue: Brake Signal to Trailer Connector
Red/Black: Battery
Light Blue/White: Brake Switch
White: Ground
It should be installed by your dealer or a qualied
service center.
If your vehicle is equipped with an ITBC, the blunt cuts
exist, but are not connected further in the harness. If
you install an aftermarket trailer brake controller,
the ITBC must be disconnected. Do not power both
ITBC and aftermarket controllers to control the trailer
brakes at the same time.
Auxiliary Battery
The auxiliary battery provision can be used to supply
electrical power to additional equipment that you
may choose to add, such as a slide-in camper. If your
vehicle has this provision, this relay will be located
on the driver’s side of the vehicle, next to the underhood
electrical center.
Be sure to follow the proper installation instructions that
are included with any electrical equipment that you
install.
Notice:Leaving electrical equipment on for
extended periods will drain the battery. Always turn
off electrical equipment when not in use and do
not use equipment that exceeds the maximum
amperage rating for the auxiliary battery provision.
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Fuses Usage
27 Passenger Side Park Lamps
28 Fog Lamps
29 Horn
30Passenger Side High-Beam
Headlamp
31 Daytime Running Lamps
32 Driver Side High-Beam Headlamp
33 Daytime Running Lights 2
34 Sunroof
35Key Ignition System, Theft Deterrent
System
36 Windshield Wiper
37 SEO B2 Uptter Usage (Battery)
38 Electric Adjustable Pedals
39 Climate Controls (Battery)
40 Airbag System (Ignition)
41 Amplier
42 Audio System
43Miscellaneous (Ignition), Cruise
ControlFuses Usage
44 Not Used
45 Airbag System (Battery)
46 Instrument Panel Cluster
47 Power Take-Off
48Auxiliary Climate Control (Ignition),
Compass-Temperature Mirror
49Center High-Mounted Stoplamp
(CHMSL)
50 Rear Defogger
51 Heated Mirrors
52 SEO B1 Uptter Usage (Battery)
53Cigarette Lighter, Auxiliary Power
Outlet
54Automatic Level Control Compressor
Relay, SEO Uptter Usage
55 Climate Controls (Ignition)
56Engine Control Module, Secondary
Fuel Pump (Ignition)
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J-Case Fuses Usage
57 Cooling Fan 1
58 Not Used
59 Heavy Duty Antilock Brake System
60 Cooling Fan 2
61 Antilock Brake System 1
62 Starter
63 Stud 2 (Trailer Brakes)
64 Left Bussed Electrical Center 1
65 Not Used
66 Heated Windshield Washer System
67 Four-Wheel Drive System
68Stud 1
(Trailer Connector Battery Power)
(Optional - 40A Fuse Required)
69 Mid-Bussed Electrical Center 1
70 Climate Control Blower
72 Not Used
73 Left Bussed Electrical Center 2Relays Usage
FAN HI Cooling Fan High Speed
FAN LO Cooling Fan Low Speed
ENG EXH VLV Not Used
FAN CNTRL Cooling Fan Control
HDLP LO/HID Low-Beam Headlamp
FOG LAMP Front Fog Lamps
A/C CMPRSR Air Conditioning Compressor
STRTR Starter
PWR/TRN Powertrain
FUEL PMP Fuel Pump
PRK LAMP Parking Lamps
REAR DEFOG Rear Defogger
RUN/CRANK Switched Power
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