2002 GMC SONOMA engine control

6-4 Gasoline Specifications
It is recommended that gasoline meet specifications
which were developed by the American Automobile
Manufacturers Association and endorsed by the
Canadian Vehicle Manufacturers' Association for better
vehicle performance and engine protection. Gasolines
meeting these specifications could provide improved
driveability and emission control system performance
compared to other gasolines.
In Canada, look for
the ªAuto Makers'
Choiceº label on
the pump.
Canada Only
California Fuel
If your vehicle is certified to meet California Emission
Standards (see the underhood emission control label), it
is designed to operate on fuels that meet California
specifications. If this fuel is not available in states
adopting California emissions standards, your vehicle
will operate satisfactorily on fuels meeting federal
specifications, but emission control system performance
may be affected. The malfunction indicator lamp may
turn on (see ªMalfunction Indicator Lampº in the Index)
and your vehicle may fail a smog
-check test. If this
occurs, return to your authorized GM dealer for
diagnosis. If it is determined that the condition is caused
by the type of fuel used, repairs may not be covered by
your warranty.
Additives
Some gasolines that are not reformulated for low
emissions may contain an octane
-enhancing additive
called methylcyclopentadienyl manganese tricarbonyl
(MMT); ask the attendant where you buy gasoline
whether the fuel contains MMT. General Motors
does not recommend the use of such gasolines.

6-5
Fuels containing MMT can reduce the life of spark
plugs and the performance of the emission control
system may be affected. The malfunction indicator lamp
may turn on. If this occurs, return to your authorized
GM dealer for service.
To provide cleaner air, all gasolines in the United States
are now required to contain additives that will help
prevent engine and fuel system deposits from forming,
allowing your emission control system to work properly.
You should not have to add anything to your fuel.
Gasolines containing oxygenates, such as ethers and
ethanol, and reformulated gasolines may be available in
your area to contribute to clean air. General Motors
recommends that you use these gasolines, particularly if
they comply with the specifications described earlier.
NOTICE:
Your vehicle was not designed for fuel that
contains methanol. Don't use fuel containing
methanol. It can corrode metal parts in your fuel
system and also damage plastic and rubber parts.
That damage wouldn't be covered under your
warranty.
Fuel E-85 (85% Ethanol)
The 8th digit of your vehicle identification number
(VIN) shows the code letter or number that identifies
your engine. You will find the VIN at the top left of the
instrument panel. See ªVehicle Identification Numberº
in the Index.
If your vehicle has the 2200 L4 engine (VIN Code 5),
you may use either regular unleaded gasoline or ethanol
fuel containing up to 85% ethanol (E
-85); also see
ªFuel (Gasoline)º listed previously. If your vehicle has
the 4.3L V6 engine use only regular unleaded gasoline.
Only vehicles with the 2200 L4 engine (VIN Code 5)
may use 85% ethanol fuel (E
-85).
Many service stations will not have an 85% ethanol
fuel (E
-85) pump available. The U. S. Department
of Energy has an alternative fuels website
(http://afdcmap.nrel.gov/nrel/) that can help you find E
-85
fuel. Those stations that do have E
-85 should have a label
indicating ethanol content. Do not use the fuel if the
ethanol content is greater than 85%. Your vehicle may not
operate properly if the ethanol content is greater than 85%.
At a minimum, E
-85 should meet
ASTM Specification D 5798.

6-68
Fuse/Circuit
BreakerUsage
A Not Used
B Not Used
1 Not Used
2 Cigarette Lighter, Data Link
ConnectorFuse/Circuit
BreakerUsage
3 Cruise Control, Body Controls
TBC, Cruise Module, Cruise
Switch
4 Gages, Body Controls TBC,
Instrument Panel Cluster,
B+ Power
5 Parking Lamps, Power Window
Switch, TBC, Ashtray Lamp
6 Steering Wheel, Illumination
7 Headlamp Switch, Body Controls
TBC, Headlamp Relay
8 Courtesy Lamps, Inadvertent
Power Relay
9 HVAC Control Head
10 Turn Signal
11 Instrument Panel Cluster,
Engine Controls
12 Interior Illumination
13 Auxiliary Power

6-69
Fuse/Circuit
BreakerUsage
14 Power Locks
15 4WD Switch, Engine Control
(VCM, PCM, Transmission)
16 Supplemental Inflatable Restraint
17 Front Wiper
18 Steering Wheel, Radio, Ignition
19 Radio Battery
20 Amplifier
21 HVAC I, HVAC Control Head,
HVAC Devices
22 Anti
-Lock Brakes
23 Rear Wiper
24 Radio, Ignition
Engine Compartment Fuse Block
The fuse block is located under the hood on the driver's
side of the engine compartment. See ªEngine
Compartment Overviewº in the Index for more
information on location.
Remove the cover by turning the fastener
counterclockwise. To reinstall the fuse panel cover,
push in and turn the fastener clockwise.

6-70
Name Usage
TRL TRN Not Used
TRR TRN Not Used
TRL B/U Not Used
VEH B/U Vehicle Back
-Up Lamps
RT TURN Right Turn Signal FrontName Usage
LT TURN Left Turn Signal Front
HDLP W/W Not Used
LT TRN Left Turn Signal Rear
RT TRN Right Turn Signal Rear
RR PRK Right Rear Parking Lamps
TRL PRK Not Used
LT HDLP Left Headlamp
RT HDLP Right Headlamp
FR PRK Front Parking Lamps
INT BAT I/P Fuse Block Feed
ENG I Engine Sensors/Solenoids, MAF,
CAM, PURGE, VENT
ECM B Engine Control Module, Fuel
Pump Module, Oil Pressure
ABS Anti
-Lock Brake System
ECM I Engine Control Module Injectors
BTSI Automatic Transmission Shift
Lock Control System

Short Trip/City Scheduled Maintenance
7-9
3,000 Miles (5 000 km)

Change engine oil and filter (or every 3 months, whichever occurs first).
An Emission Control Service.

Lubricate chassis components (or every 3 months, whichever occurs first).
(See footnote #.)

Check rear/front axle fluid level and add fluid as needed. Check constant
velocity joints and axle seals for leaking. (See footnote **.)
6,000 Miles (10 000 km)

Change engine oil and filter (or every 3 months, whichever occurs first).
An Emission Control Service.

Lubricate chassis components (or every 3 months, whichever occurs first).
(See footnote #.)

Check rear/front axle fluid level and add fluid as needed. Check constant
velocity joints and axle seals for leaking. (See footnote **.)

Rotate tires. See ªTire Inspection and Rotationº in the Index for proper
rotation pattern and additional information. (See footnote +.)
ACTUAL
SERVICED BY:MILEAGE
DATE
ACTUAL
SERVICED BY:MILEAGE
DATE

Short Trip/City Scheduled Maintenance
7-10
9,000 Miles (15 000 km)

Change engine oil and filter (or every 3 months, whichever occurs first).
An Emission Control Service.

Lubricate chassis components (or every 3 months, whichever occurs first).
(See footnote #.)

Check rear/front axle fluid level and add fluid as needed. Check constant
velocity joints and axle seals for leaking. (See footnote **.)
12,000 Miles (20 000 km)

Change engine oil and filter (or every 3 months, whichever occurs first).
An Emission Control Service.

Lubricate chassis components (or every 3 months, whichever occurs first).
(See footnote #.)

Check rear/front axle fluid level and add fluid as needed. Check constant
velocity joints and axle seals for leaking. (See footnote **.)

Rotate tires. See ªTire Inspection and Rotationº in the Index for proper
rotation pattern and additional information. (See footnote +.)
ACTUAL
SERVICED BY:MILEAGE
DATE
ACTUAL
SERVICED BY:MILEAGE
DATE

Short Trip/City Scheduled Maintenance
7-11
15,000 Miles (25 000 km)

Change engine oil and filter (or every 3 months, whichever occurs first).
An Emission Control Service.

Lubricate chassis components (or every 3 months, whichever occurs first).
(See footnote #.)

Inspect engine air cleaner filter if you are driving in dusty conditions.
Replace filter if necessary.
An Emission Control Service. (See footnote
.)
Check rear/front axle fluid level and add fluid as needed. Check constant
velocity joints and axle seals for leaking. (See footnote **.)
For Two
-Wheel-Drive vehicles only: Clean and repack the front wheel
bearings (or at each brake relining, whichever occurs first).
Change automatic transmission fluid and filter if the vehicle is mainly driven
under one or more of these conditions:
± In heavy city traffic where the outside temperature regularly
reaches 90F (32C) or higher.
± In hilly or mountainous terrain.
± When doing frequent trailer towing.
± Uses such as found in taxi, police or delivery service.
If you do not use your vehicle under any of these conditions, change the fluid
and filter every 50,000 miles (83 000 km).
ACTUAL
SERVICED BY:MILEAGE
DATE