2012 GMC SIERRA 1500 engine

Black plate (13,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Instruments and Controls 5-13
For vehicles with a DURAMAX®
Diesel engine, see the DURAMAX®
Diesel Supplement for more
information.
For vehicles with a Hybrid, see the
Hybrid Supplement for more
information.
Speedometer
The speedometer shows the
vehicle's speed in either kilometers
per hour (km/h) or miles per
hour (mph).
Odometer
The odometer shows how far the
vehicle has been driven, in either
kilometers or miles.
Engine Hour Meter Display
The Driver Information Center (DIC)
can also display the number of
hours the engine has run. To display
the engine hours, turn the ignition
off, then press and hold the reset
button for at least four seconds.The hour meter displays for up to
30 seconds, or until the ignition is
turned on. See
Driver Information
Center (DIC) on page 5‑30 for more
information.
Trip Odometer
The trip odometer shows how far
the vehicle has been driven since
the trip odometer was last set
to zero.
Press the reset button, located on
the instrument panel cluster next to
the voltmeter, to toggle between
the trip odometer and the regular
odometer. Holding the reset button
for approximately one second while
the trip odometer is displayed will
reset it. To display the odometer reading
with the ignition off, press the reset
button.
See
Driver Information Center (DIC)
on page 5‑30 for more information.
Tachometer
The tachometer displays the engine
speed in revolutions per minute
(rpm). For a description of how
Grade Braking affects vehicle
speed while the Tow/Haul Mode is
activated, see Tow/Haul Mode on
page 9‑39 for more information.
If the vehicle is a hybrid, see the
hybrid supplement for more
information.

Black plate (14,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
5-14 Instruments and Controls
Fuel Gauge
Metric
EnglishWhen the ignition is on, the fuel
gauge shows about how much fuel
is left in the fuel tank.
An arrow on the fuel gauge
indicates the side of the vehicle the
fuel door is on.
The gauge will first indicate empty
before the vehicle is out of fuel, but
the vehicle's fuel tank should be
filled soon.
When the fuel tank is low the
FUEL LEVEL LOW message
appears. See
Fuel System
Messages on page 5‑43 for more
information.
Here are some situations owners
can experience with the fuel gauge.
None of these indicate a problem
with the fuel gauge.
.At the gas station, the fuel pump
shuts off before the gauge
reads full.
.It takes a little more or less fuel
to fill up than the fuel gauge
indicated. For example, the
gauge may have indicated the
tank was half full, but it actually
took a little more or less than
half the fuel tank's capacity to
fill it.
.The gauge goes back to empty
when the ignition is turned off.
If the vehicle has a diesel engine,
see the Duramax diesel supplement
for more information.
If the vehicle is a hybrid, see the
hybrid supplement for more
information.

Black plate (15,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Instruments and Controls 5-15
Engine Oil Pressure
Gauge
Metric
English
The engine oil pressure gauge
shows the engine oil pressure
in kPa (kilopascals) or psi (pounds
per square inch) when the engine is
running.
Oil pressure can vary with engine
speed, outside temperature and oil
viscosity, but if readings are outside
the normal operating range, the oil
pressure light comes on. See
Engine Oil Pressure Light on
page 5‑28 for more information. A reading outside the normal
operating range can be caused by a
dangerously low oil level or some
other problem causing low oil
pressure. Check the vehicle's
oil as soon as possible. See
“OIL
PRESSURE LOW STOP ENGINE”
under Engine Oil Messages on
page 5‑42 andEngine Oil on
page 10‑7.
Notice: Lack of proper engine oil
maintenance can damage the
engine. Driving with the engine
oil low can also damage the
engine. The repairs would not be
covered by the vehicle warranty.
Check the oil level as soon as
possible. Add oil if required,
but if the oil level is within the
operating range and the oil
pressure is still low, have the
vehicle serviced. Always follow
the maintenance schedule for
changing engine oil.
If the vehicle has a diesel engine,
see the Duramax diesel supplement
for more information.

Black plate (16,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
5-16 Instruments and Controls
If the vehicle is a hybrid, see the
hybrid supplement for more
information.
Engine Coolant
Temperature Gauge
Metric
English
This gauge shows the engine
coolant temperature.
It also provides an indicator of how
hard the vehicle is working. During
a majority of the operation, the
gauge reads 100°C (210°F) or less.
If pulling a load or going up hills, it
is normal for the temperature to
fluctuate and go over the 113°C
(235°F) mark. If the gauge reaches
the 125°C (260°F) mark, it indicates
that the cooling system is working
beyond its capacity. See
Engine Overheating on
page 10‑22.
If the vehicle is a hybrid, see the
hybrid supplement for more
information.
Voltmeter Gauge
This gauge indicates the battery
voltage when the ignition is
turned on.
When the ignition is on, this gauge
indicates the battery voltage.

Black plate (17,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Instruments and Controls 5-17
When the engine is running, this
gauge shows the condition of the
charging system. The gauge can
transition from a higher to lower or a
lower to higher reading. This is
normal. If the vehicle is operating
outside the normal operating range,
the charging system light comes on.
SeeCharging System Light on
page 5‑22 for more information. The
voltmeter gauge may also read
lower when in fuel economy mode.
This is normal.
Readings outside the normal
operating range can also occur
when a large number of electrical
accessories are operating in the
vehicle and the engine is left idling
for an extended period. This
condition is normal since the
charging system is not able to
provide full power 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.
The vehicle can only be driven for a
short time with the readings outside
the normal operating range. If the
vehicle must be driven, turn off all
accessories, such as the radio and
air conditioner.
Readings outside the normal
operating range indicate a possible
problem in the electrical system.
Have the vehicle serviced as soon
as possible.Safety Belt Reminders
Driver Safety Belt Reminder
Light
There is a driver safety belt
reminder light on the instrument
panel cluster.
When the vehicle is started, this
light flashes and a chime may come
on to remind the driver to fasten
their safety belt. Then the light stays
on solid until the belt is buckled.
This cycle my continue several
times if the driver remains or
becomes unbuckled while the
vehicle is moving.
If the driver safety belt is buckled,
neither the light nor the chime
comes on.

Black plate (18,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
5-18 Instruments and Controls
Passenger Safety Belt
Reminder Light
For vehicles equipped with the
passenger safety belt reminder
light, several seconds after the
engine is started, a chime sounds
for several seconds to remind the
front passenger to buckle their
safety belt. The passenger safety
belt light flashes and then stays on
solid until the belt is buckled. This
cycle continues several times if the
passenger remains or becomes
unbuckled while the vehicle is
moving.
If the passenger safety belt is
buckled, neither the chime nor the
light comes on.The front passenger safety belt
warning light and chime may turn on
if an object is put on the seat such
as a briefcase, handbag, grocery
bag, laptop, or other electronic
device. To turn off the warning light
and/or chime, remove the object
from the seat or buckle the
safety belt.Airbag Readiness Light
The system checks the airbag's
electrical system for possible
malfunctions. If the light stays on
it indicates there is an electrical
problem. The system check
includes the airbag sensor(s), the
pretensioners, the airbag modules,
the wiring, and the crash sensing
and diagnostic module. For more
information on the airbag system,
see
Airbag System on page 3‑21.
The airbag readiness light comes on
solid for a few seconds when the
engine is started. If the light does
not come on then, have it fixed
immediately.
{WARNING
If the airbag readiness light stays
on after the vehicle is started or
comes on while driving, it means
the airbag system might not be
working properly. The airbags in
the vehicle might not inflate in a
crash, or they could even inflate
without a crash. To help avoid
injury, have the vehicle serviced
right away.

Black plate (22,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
5-22 Instruments and Controls
If, after several seconds, both status
indicator lights remain on, or if there
are no lights at all, there may be a
problem with the lights or the
passenger sensing system. See
your dealer for service.
{WARNING
If the airbag readiness light ever
comes on and stays on, it means
that something may be wrong
with the airbag system. To help
avoid injury to yourself or others,
have the vehicle serviced right
away. SeeAirbag Readiness
Light on page 5‑18 for more
information, including important
safety information.
Charging System Light
This light comes on briefly when the
ignition key is turned to START, but
the engine is not running, as a
check to show it is working.
If it does not, have the vehicle
serviced by your dealer.
The light should go out once
the engine starts. If it stays on,
or comes on while driving, there
could be a problem with the
charging system. A charging system
message in the Driver Information
Center (DIC) can also appear. See
Battery Voltage and Charging
Messages on page 5‑39 for more
information. This light could indicate
that there are problems with a
generator drive belt, or that there
is an electrical problem. Have it checked right away. If the vehicle
must be driven a short distance with
the light on, turn off accessories,
such as the radio and air
conditioner.
If the vehicle is a hybrid, see the
hybrid supplement for more
information.Malfunction
Indicator Lamp
A computer system called OBD II
(On-Board Diagnostics-Second
Generation) monitors the operation
of the vehicle to ensure emissions
are at acceptable levels, to produce
a cleaner environment. This light
comes on when the vehicle is
placed in ON/RUN, as a check to
show it is working. If it does not,
have the vehicle serviced by your
dealer. See
Ignition Positions on
page 9‑26.

Black plate (23,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Instruments and Controls 5-23
If the malfunction indicator lamp
comes on and stays on while the
engine is running, this indicates that
there is an OBD II problem and
service is required.
Malfunctions often are indicated by
the system before any problem is
apparent. Being aware of the light
can prevent more serious damage
to the vehicle. This system assists
the service technician in correctly
diagnosing any malfunction.
Notice:If the vehicle is
continually driven with this light
on, the emission controls might
not work as well, the vehicle fuel
economy might not be as good,
and the engine might not run as
smoothly. This could lead to
costly repairs that might not be
covered by the vehicle warranty. Notice:
Modifications made
to the engine, transmission,
exhaust, intake, or fuel system
of the vehicle or the replacement
of the original tires with other
than those of the same Tire
Performance Criteria (TPC) can
affect the vehicle's emission
controls and can cause this light
to come on. Modifications to
these systems could lead to
costly repairs not covered by
the vehicle warranty. This could
also result in a failure to pass a
required Emission Inspection/
Maintenance test. See
Accessories and Modifications on
page 10‑3.
This light comes on during a
malfunction in one of two ways:
Light Flashing: A misfire condition
has been detected. A misfire
increases vehicle emissions and
could damage the emission control
system on the vehicle. Diagnosis
and service might be required. To prevent more serious damage to
the vehicle:
.Reduce vehicle speed.
.Avoid hard accelerations.
.Avoid steep uphill grades.
.If towing a trailer, reduce the
amount of cargo being hauled as
soon as it is possible.
If the light continues to flash, stop
and park the vehicle. Turn the
vehicle off, wait at least 10 seconds,
and restart the engine. If the light is
still flashing, follow the previous
steps and see your dealer for
service as soon as possible.
Light On Steady: An emission
control system malfunction has
been detected on the vehicle.
Diagnosis and service might be
required.