2003 GMC SONOMA brake sensor

;(Parking Lamps):Turning the exterior lamps
control to this position turns on the parking lamps
together with the following:
Sidemarker Lamps
Taillamps
License Plate Lamps
Instrument Panel Lights
O(Headlamps):Turning the exterior lamps control to
this position turns on the headlamps, together with
the previously listed lamps and lights.
Automatic Headlamp System
When it is dark enough outside, your automatic
headlamp system will turn on your headlamps at the
normal brightness along with other lamps such as
the taillamps, sidemarker, parking lamps and the
instrument panel lights. The radio lights will also be dim.
Your vehicle is equipped with a light sensor on the
top of the instrument panel under the radio speaker grill.
Be sure it is not covered or the system will be on
whenever the ignition is on.
The system may also turn on your headlamps when
driving through a parking garage, heavy overcast
weather or a tunnel. This is normal.There is a delay in the transition between the daytime
and nighttime operation of the Daytime Running
Lamps (DRL) and the automatic headlamp systems so
that driving under bridges or bright overhead street
lights does not affect the system. The DRL and
automatic headlamp system will only be affected when
the light sensor sees a change in lighting lasting
longer than the delay.
To idle your vehicle with the automatic headlamp
system off, set the parking brake while the ignition is off.
Then start your vehicle. The automatic headlamp
system will stay off until you release the parking brake.
As with any vehicle, you should turn on the regular
headlamps when you need them.
You may be able to turn off your automatic headlamp
system. See“Daytime Running Lamps (DRL)”later
in this section for more information.
If you start your vehicle in a dark garage, the automatic
headlamp system will come on immediately. Once
you leave the garage, it will take approximately
one minute for the automatic headlamp system to
change to DRL if it is light outside. During that delay,
your instrument panel cluster may not be as bright
as usual. Make sure your instrument panel brightness
control is in the full bright position. See“Instrument
Panel Brightness Control”underInterior Lamps
on page 3-14.
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2003 - Sonoma OM

Lamps On Reminder
A reminder chime will sound when your headlamps or
parking lamps are manually turned on, the driver’s door
is opened and your ignition is in OFF, LOCK or
ACCESSORY. To turn the chime off, turn the control
counterclockwise or turn the instrument panel brightness
thumbwheel down to the fully dimmed position. In the
automatic mode, the headlamps turn off once the ignition
key is in OFF.
Daytime Running Lamps
Daytime Running Lamps (DRL) can make it easier for
others to see the front of your vehicle during the
day. DRL can be helpful in many different driving
conditions, but they can be especially helpful in the short
periods after dawn and before sunset. Fully functional
daytime running lamps are required on all vehicles
rst sold in Canada.The DRL system will make your headlamps come on
at reduced brightness when the following conditions
are met:
The ignition is on,
the exterior lamp control is in OFF,
the sensor detects daytime light,
an automatic transmission is not in PARK (P), and
the parking brake is released.
When the DRL are on, only your headlamps will be on.
The taillamps, sidemarker and other lamps won’tbe
on. The instrument panel won’t be lit up either.
When it begins to get dark, the headlamps will
automatically switch from DRL to the regular headlamps.
The DRL system on some vehicles may turn off
temporarily while the turn signals are activated.
To idle an automatic transmission vehicle with the DRL
off, put the transmission in PARK (P). To idle a
manual transmission vehicle with the DRL off, set the
parking brake. The DRL will stay off until you shift out of
PARK (P) or release the parking brake.
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2003 - Sonoma OM

Fuse Usage
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, IgnitionEngine Compartment Fuse Block
The engine compartment fuse block is located under
the hood on the driver’s side of the vehicle. SeeEngine
Compartment Overview on page 5-10for 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.
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2003 - Sonoma OM

Fuse Usage
TRL TRN Trailer Left Turn
TRR TRN Trailer Right Turn
TRL B/U Trailer Back Up Lamps
VEH B/U Vehicle Back Up Lamps
HDLP PWR Headlamp PowerFuse Usage
RT TURN Right Turn Signal Front
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 Trailer Park Lamps
LTHDLP Left Headlamp
RTHDLP Right Headlamp
FRPRK Front Parking Lamps
INT BAT Instrument Panel 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
F/PUMP Fuel Pump
DRL Daytime Running Lamps
A/C Air Conditioning
HORN Horn
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2003 - Sonoma OM

Fuse Usage
W/W PMP Not Used
HORN Horn
BTSI Automatic Transmission Shift Lock
Control System
B/U LP Back Up Lamps
IGN B Column Feed,Ignition 2, 3, 4
STARTER Starter
RAP Retained Accessory Power
LD LEV Not Used
OXYSEN Oxygen Sensor
IGN E Engine
MIR/LKS Mirrors, Door Locks
FOG LP Fog Lamps
IGN A Starting and Charging Ignition 1
STUD #2 Accessory Feeds, Electric Brake
PARKLP Parking Lamps
LR PRK Left Rear Parking Lamps
LIFTGLASS Liftglass
IGN C Starter Solenoid, Fuel Pump,
PRNDL
HTDSEAT Heated SeatFuse Usage
HVAC Heating,Ventilation, Air Cooling
System
TRCHMSL Trailer Center High Mount Stop Light
RRDFOG Rear Defogger
TBC Truck Body Computer
CRANK Clutch Switch, NSBU Switch
CHMSL Center High Mounted Stoplamp
HAZLP Hazard Lamps
VECHMSL Vehicle Center High-Mounted
Stop Lamp
RR DEFOG Rear Defogger
HTDMIR Heated Mirror
ATC Transfer Case (Four-Wheel Drive)
STOPLP Stop Lamps
RR W/W Rear Window Wiper
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2003 - Sonoma OM