2005 GMC JIMMY brake light

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. SeeDaytime Running Lamps (DRL) on
page 3-15later 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. SeeInstrument Panel
Brightness on page 3-18.Fog Lamps
Your vehicle may be equipped with fog lamps. Use your
fog lamps for better vision in foggy or misty conditions.
Your parking lamps or headlamps must be on for
your fog lamps to work.
The fog lamp button is located on the instrument panel
near the lamp control.
Press the button to turn the fog lamps on. Press the
button again to turn them off. A light will glow in
the button 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.
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at engine idle. As engine speeds are increased, this
condition should correct itself as higher engine speeds
allow the charging system to create maximum power.
You can only drive for a short time with the reading
in either warning zone. If you must drive, turn off
all unnecessary accessories. Readings in either warning
zone indicate a possible problem in the electrical
system. Have the vehicle serviced as soon as possible.
Up-Shift Light
Shifting when the indicator light is on will help you get
the best fuel economy. See “Up-Shift Light” under
Manual Transmission Operation on page 2-29.
Brake System Warning Light
When the ignition is on, the brake system warning light
will come on when you set your parking brake. The
light will stay on if your parking brake doesn’t release
fully. If it stays on after your parking brake is fully
released, it means you have a brake problem.
Your vehicle’s hydraulic brake system is divided into
two parts. If one part isn’t working, the other part can still
work and stop you. For good braking, though, you
need both parts working well.
If the warning light comes on, there could be a brake
problem. Have your brake system inspected right away.
This light should come on briey when you turn the
ignition key to RUN. If it doesn’t come on then, have it
xed so it will be ready to warn you if there’s a
problem. United States
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If the light comes on while you are driving, pull off the
road and stop carefully. You may notice that the pedal is
harder to push. Or, the pedal may go closer to the
oor. It may take longer to stop. If the light is still on,
have the vehicle towed for service. SeeTowing
Your Vehicle on page 4-49.
{CAUTION:
Your brake system may not be working
properly if the brake system warning light is
on. Driving with the brake system warning light
on can lead to an accident. If the light is still
on after you have pulled off the road and
stopped carefully, have the vehicle towed for
service.
Anti-Lock Brake System
Warning Light
With the anti-lock brake
system, this light will
come on when you start
your engine and may
stay on for several
seconds. That’s normal.
If the light stays on, or comes on when you’re driving,
your vehicle needs service. If the regular brake
system warning light isn’t on, you still have brakes, but
you don’t have anti-lock brakes. If the regular brake
system warning light is also on, you don’t have anti-lock
brakes and there’s a problem with your regular
brakes. SeeBrake System Warning Light on page 3-29.
The anti-lock brake system warning light should come
on briey when you turn the ignition key to RUN. If
the light doesn’t come on then, have it xed so it will be
ready to warn you if there is a problem.
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Anti-Lock Brake System (ABS)
Your vehicle has anti-lock brakes. ABS is an advanced
electronic braking system that will help prevent a
braking skid.
When you start your engine and begin to drive away,
your anti-lock brake system will check itself. You
may hear a momentary motor or clicking noise while
this test is going on. This is normal.
If there is a problem with
the anti-lock brake system,
this warning light will
stay on. SeeAnti-Lock
Brake System Warning
Light on page 3-30.
Let us say the road is wet and you are driving safely.
Suddenly, an animal jumps out in front of you. You slam
on the brakes and continue braking. Here is what
happens with ABS:
A computer senses that wheels are slowing down. If
one of the wheels is about to stop rolling, the computer
will separately work the brakes at each front wheel
and at both rear wheels.
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Driving Downhill
When off-roading takes you downhill, you will want to
consider a number of things:
How steep is the downhill? Will I be able to maintain
vehicle control?
What is the surface like? Smooth? Rough?
Slippery? Hard-packed dirt? Gravel?
Are there hidden surface obstacles? Ruts? Logs?
Boulders?
What is at the bottom of the hill? Is there a hidden
creek bank or even a river bottom with large rocks?
If you decide you can go down a hill safely, then try to
keep your vehicle headed straight down, and use a
low gear. This way, engine drag can help your brakes
and they will not have to do all the work. Descend
slowly, keeping your vehicle under control at all times.
{CAUTION:
Heavy braking when going down a hill can
cause your brakes to overheat and fade. This
could cause loss of control and a serious
accident. Apply the brakes lightly when
descending a hill and use a low gear to keep
vehicle speed under control.
Q:Are there some things I should not do when
driving down a hill?
A:Yes! These are important because if you ignore
them you could lose control and have a serious
accident.
When driving downhill, avoid turns that take you
across the incline of the hill. A hill that is not too
steep to drive down may be too steep to drive
across. You could roll over if you do not drive
straight down.
Never go downhill with the transmission in
NEUTRAL (N), or with the clutch pedal pressed
down in a manual shift. This is called
“free-wheeling.” Your brakes will have to do all the
work and could overheat and fade.
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{CAUTION:
Wet brakes can cause accidents. They will not
work as well in a quick stop and may cause
pulling to one side. You could lose control of
the vehicle.
After driving through a large puddle of water
or a car wash, apply your brake pedal lightly
until your brakes work normally.
Hydroplaning
Hydroplaning is dangerous. So much water can build up
under your tires that they can actually ride on the
water. This can happen if the road is wet enough and
you are going fast enough. When your vehicle is
hydroplaning, it has little or no contact with the road.Hydroplaning does not happen often. But it can if your
tires do not have much tread or if the pressure in one or
more is low. It can happen if a lot of water is standing
on the road. If you can see reections from trees,
telephone poles, or other vehicles, and raindrops dimple
the water’s surface, there could be hydroplaning.
Hydroplaning usually happens at higher speeds. There
just is not a hard and fast rule about hydroplaning.
The best advice is to slow down when it is raining.
Driving Through Deep Standing Water
Notice:If you drive too quickly through deep
puddles or standing water, water can come in
through your engine’s air intake and badly damage
your engine. Never drive through water that is
slightly lower than the underbody of your vehicle. If
you cannot avoid deep puddles or standing water,
drive through them very slowly.
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Driving On Grades
Reduce speed and shift to a lower gearbeforeyou start
down a long or steep downgrade. If you don’t shift
down, you might have to use your brakes so much that
they would get hot and no longer work well.
If you have an automatic transmission, you can tow in
DRIVE (D). You may want to shift the transmission
to THIRD (3) or, if necessary, a lower gear selection if
the transmission shifts too often (e.g., under heavy loads
and/or hilly conditions). Or, if you have a manual
transmission and you are towing a trailer, it’s better not
to use FIFTH (5) gear. Just drive in FOURTH (4)
gear (or, as you need to, a lower gear). SeeTow/Haul
Mode Light on page 3-36.
When towing at high altitude on steep uphill grades,
consider the following: Engine coolant will boil at a lower
temperature than at normal altitudes. If you turn your
engine off immediately after towing at high altitude
on steep uphill grades, your vehicle may show signs
similar to engine overheating. To avoid this, let the
engine run while parked (preferably on level ground)
with the automatic transmission in PARK (P) (or
the manual transmission out of gear and the parking
brake applied) for a few minutes before turning the
engine off. If you do get the overheat warning,
seeEngine Overheating on page 5-26.
Parking on Hills
{CAUTION:
You really should not park your vehicle, with a
trailer attached, on a hill. If something goes
wrong, your rig could start to move. People
can be injured, and both your vehicle and the
trailer can be damaged.
But if you ever have to park your rig on a hill, here’s
how to do it:
1. Apply your regular brakes, but don’t shift into
PARK (P) yet, or into gear for a manual
transmission. Then turn your wheels into the curb if
facing downhill or into traffic if facing uphill.
2. Have someone place chocks under the
trailer wheels.
3. When the wheel chocks are in place, release the
regular brakes until the chocks absorb the load.
4. Reapply the regular brakes. Then apply your
parking brake, and then shift into PARK (P), or
REVERSE (R) for a manual transmission.
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Trailer Wiring Harness
The light-duty trailer wiring is a six-wire harness
assembly. The optional heavy-duty trailer wiring is an
eight-wire harness assembly. The harnesses are stored
under the vehicle, along the passenger-side frame
crossmember on two-door vehicles or on the driver’s
side corner frame rear crossmember on four-door
vehicles. The heavy-duty trailer wiring is fused in the
engine compartment fuse block. SeeFuses and Circuit
Breakers on page 5-90. Both harnesses have no
connector and should be wired by a qualied electrical
technician. The technician can use the following
color code chart when connecting the wiring harness to
your trailer.
Dark Blue: Use for electric trailer brakes or auxiliary
wiring (eight-wire harness only).
Red: Use for battery charging; it connects to the
starter solenoid (eight-wire harness only).
Light Green: Back-up lamps.
Brown: Taillamps and parking lamps.
Yellow: Driver’s side stoplamp and turn signal.
Dark Green: Passenger’s side stoplamp
and turn signal.
White: Ground wire.
Light Blue: Auxiliary stoplamp.
Securely attach the harness to the trailer, then tape or
strap it to your vehicle’s frame rail. Be sure you
leave it loose enough so the wiring doesn’t bend or
break, but not so loose that it drags on the ground. Store
the harness in its original place. Wrap the harness
together and tie it neatly so it won’t be damaged.
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