2000 GMC JIMMY brake sensor

2-50 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
headlamp system when you need it.
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 knob all
the way to the left or turn the instrument panel dimmer
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.

2-51
The DRL system will make your headlamps come on at
reduced brightness when:

the ignition is on,

the headlamp switch is in automatic headlamp mode,

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't be 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.
As with any vehicle, you should turn on the regular
headlamp system when you need it.Fog Lamps (If Equipped)
Use your fog lamps for better vision in foggy or misty
conditions. Your parking lamps must be on for your fog
lamps to work.
The fog lamp switch is on the instrument panel under
the lamps switch. Press the switch to turn the fog lamps
on. Press the switch again to turn them off. A light will
glow in the switch when the fog lamps are on.
Fog lamps will go off whenever your high
-beam
headlamps come on. When the high beams go off, the
fog lamps will come on again.

6-61
Fuse/Circuit
BreakerUsage
A Not Used
B Not Used
1 Not Used
2 Cigarette Lighter, Data
Link Connector
3 Cruise Control Module and
Switch, Body Control Module,
Heated Seats
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 HVAC Control Head (Manual)Fuse/Circuit
BreakerUsage
10 Turn Signal
11 Cluster, Engine Control Module
12 Interior lights
13 Auxiliary Power
14 Power Locks Motor
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 HVAC (Manual), HVAC I
(Automatic), HVAC
Sensors (Automatic)
22 Anti-Lock Brakes
23 Rear Wiper
24 Radio, Ignition

6-63
Name 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
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 LampsName Usage
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
A/C Air Conditioning
W/W PMP Not Used
HORN Horn
BTSI Automatic Transmission Shift
Lock Control System
B/U LP Back Up Lamps
IGN B Column Feed, IGN 2, 3, 4
RAP Retained Accessory Power

6-64
Name Usage
LD LEV Not Used
OXYSEN Oxygen Sensor
IGN E Engine
MIR/LKS Mirrors, Door Locks
FOG LP Fog Lamps
IGN A Starting and Charging IGN 1
STUD #2 Accessory Feeds, Electric Brake
PARKLP Parking Lamps
LR PRK Left Rear Parking Lamps
IGN C Starter Solenoid, Fuel
Pump, PRNDL
HTDSEAT Heated Seat
HVAC HVAC SystemName Usage
TRCHMSL Trailer Center High Mount
Stop Light
RRDFOG Rear Defogger
TBC Truck Body Computer
CRANK Clutch Switch, NSBU Switch
HAZLP Hazard Lamps
VECHMSL Vehicle Center High
-Mounted
Stop Lamp
HTDMIR Heated Mirror
ATC Transfer Case (Four
-Wheel Drive)
STOPLP Stop Lamps
RR W/W Rear Window Wiper