2004 GMC SONOMA 4WD

Security Light
This light will come on
briefly when you turn the
key toward START.
The light will stay on until
the engine starts.
If the light flashes, the Passlock
®system has entered a
tamper mode. If the vehicle fails to start, seePasslock®
on page 2-16.
If the light comes on continuously while driving and
stays on, there may be a problem with the Passlock
®
system. Your vehicle will not be protected by Passlock®,
and you should see your dealer.
Also, seeContent Theft-Deterrent on page 2-14for
additional information regarding the SECURITY light.
Service Four-Wheel Drive
Warning Light
If you have this light, it
should come on briefly
when you turn on the
ignition, as a check
to show you it is working.
The SERVICE 4WD light comes on to indicate that
there may be a problem with the four-wheel drive system
and service is required. Malfunctions can be indicated
by the system before any problem is apparent,
which may prevent serious damage to the vehicle. This
system is also designed to assist your service
technician in correctly diagnosing a malfunction.
3-33

Vehicle* Axle RatioMaximum Trailer
WeightGCWR**
4WD Crew Cab®
4.3L V6/Auto. Trans.3.42
3.735,200 lbs. (2 361 kg)
5,200 lbs. (2 361 kg)9,500 lbs. (4 309 kg)
9,500 lbs. (4 309 kg)
* If your vehicle is equipped with RPO V4A (Xtreme™
Sport Appearance Package), your vehicle was
neither intended nor designed to tow a trailer. For more
information on RPO codes, seeService Parts
Identication Label on page 5-94.
**The Gross Combination Weight Rating (GCWR) is the
total allowable weight of the completely loaded vehicle
and trailer including any passengers, cargo, equipment
and conversions. The GCWR for your vehicle should
not be exceeded.
You can ask your dealer for our trailering information or
advice, or you can write us at the address listed in
your Warranty and Owner Assistance Information
Booklet.
In Canada, write to:
General Motors of Canada Limited
Customer Communication Centre, 163-005
1908 Colonel Sam Drive
Oshawa, Ontario L1H 8P7
Weight of the Trailer Tongue
The tongue load (A) of any trailer is an important weight
to measure because it affects the total or gross weight
of your vehicle. The Gross Vehicle Weight (GVW)
includes the curb weight of the vehicle, any cargo you
may carry in it, and the people who will be riding in
the vehicle. If you have a lot of options, equipment,
passengers or cargo in your vehicle, it will reduce the
tongue weight your vehicle can carry, which will
also reduce the trailer weight your vehicle can tow. And
if you will tow a trailer, you must add the tongue load
to the GVW because your vehicle will be carrying
that weight, too. SeeLoading Your Vehicle on page 4-45
for more information about your vehicle’s maximum
load capacity.
4-57

Fuse Usage
4 Gages, Body Control Module,
Instrument Panel Cluster
5 Parking Lamps, Power Window
Switch, Body Control Module,
Ashtray Lamp
6 Steering Wheel Radio Controls
7 Headlamps Switch, Body Control
Module, Headlamp Relay
8 Courtesy Lamps, Battery Run-Down
Protection
9 Heating, Ventilation, Air Cooling
Control Head (Manual)
10 Turn Signal
11 Cluster, Engine Control Module
12 Interior Lights
13 Auxiliary Power
14 Power Locks MotorFuse Usage
15 4WD Switch, Engine Controls (VCM,
PCM, Transmission)
16 Supplemental Inflatable Restraint
17 Front Wiper
18 Steering Wheel Radio Controls
19 Radio, Battery
20 Amplifier
21 Heating, Ventilation, Air Cooling
(Manual), Heating,Ventilation, Air
Cooling (Automatic), Heating,
Ventilation, Air Cooling Sensors
(Automatic)
22 Anti-Lock Brakes
23 Rear Wiper
24 Radio, Ignition
5-97