1999 GMC SAFARI brake sensor

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Turn the knob clockwise to the master lighting symbol
to turn on all the lamps listed as well as the headlamps.
Turn the knob all the way counterclockwise to turn off
your lamps and put the system in auto headlamp mode.
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 in the defroster grille. 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 lightning 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
headlamp system when you need it.Lamps On Reminder
A reminder tone will sound when your headlamps or
parking lamps are manually turned on and your ignition
is in the OFF, LOCK or ACCESSORY position. To
disable the tone, turn the thumbwheel all the way down.
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.

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The DRL system will make your headlamps come on at
a reduced brightness when:

the ignition is on,

the headlamp switch is in automatic headlamp mode.

the automatic transmission is not in PARK (P),

the light sensor determines it is daytime and

the parking brake is released.
When the DRL are on, only your DRL lamps will be on.
The taillamps, sidemarker and other lamps won't be on.
Your instrument panel won't be lit up either.
When it begins to get dark, the automatic headlamp
system will switch from DRL to the headlamps or the
last chosen headlamp setting that was used.
To idle the vehicle with the DRL off, set the parking
brake. Shifting the transmission into PARK (P) will
also allow you to idle the vehicle with the DRL off.
The DRL will stay off until you release the parking
brake or shift the transmission out of PARK (P).
As with any vehicle, you should turn on the regular
headlamp system when you need it.Interior Lamps
Instrument Panel Intensity Control
The instrument panel intensity control is located to the
right of the headlamp switch.
Turn the thumbwheel up to adjust the instrument panel
lights. To turn on the dome lamps (with the vehicle
doors closed) turn the thumbwheel all the way up.
Exit Lighting
With exit lighting, the interior lamps will come on when
you remove the key from the ignition. The lights will
not come on if the DOME OVERRIDE button is
pressed in.
Illuminated Entry
Your vehicle is equipped with an illuminated entry feature.
When the doors are opened, the dome lamps will come
on if the DOME OVERRIDE button is in the ªoutº
position. When all the doors are closed, the lamps will
stay on for a short period of time and will then go out.
If the DOME OVERRIDE button is pressed in, the
lamps will not come on.

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Fuse/Circuit
Breaker Usage
ECM
-B Fuel Pump Relay and Motor,
VCM, Oil Pressure
Switch/Sender
HORN Horn Relay and Horn
A/C COMP A/C Enable Relay
and Compressor
RR HTR/AC Rear Heater and A/C
ATC Active Transfer Case
FRT HVAC Front Heater and A/C
ENG
-I Oxygen Sensors, Camshaft
Position Sensor, Mass Air Flow
Sensor, Evaporative Emission
Canister Vent Solenoid
IGN
-E A/C Enable Relay Coil
ECM
-I Fuel Injectors 1-6, Crankshaft
Position Sensor, VCM, Coil
Driver Module (EST),
Ignition CoilFuse/Circuit
Breaker Usage
RH HDLMP Right Headlamp
LH Headlamp Left Headlamp
DIODE
-A/C Coil A/C
LIGHTING Courtesy Fuse, Pwr. Adj.
Mirrors Fuse, TBC
-Battery Fuse
BATT Power ACCY CB, Stop/Hazard
Fuse, Auxiliary Power Fuse,
Cigarette Lighter Fuse,
Radio Battery Fuse
IGN A Starter Relay, Ignition Switch
IGN B Ignition Switch
ABS Electronic Brake
Control Module
RAP Radio Accy, Power Windows
HTD MIR/RR
DEFOGRear Window Defogger,
HVAC Control Head
*A fuse puller is included in the underhood electrical
center. You will also find spare fuses.