2012 GMC SIERRA 1500 check engine light

Black plate (3,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Keys, Doors, and Windows 2-3
If there is a decrease in the RKE
operating range:
.Check the distance. The
transmitter may be too far from
the vehicle.
.Check the location. Other
vehicles or objects may be
blocking the signal.
.Check the transmitter's battery.
See“Battery Replacement” later
in this section.
.If the transmitter is still not
working correctly, see your
dealer or a qualified technician
for service.
Remote Keyless Entry
(RKE) System Operation
The Remote Keyless Entry (RKE)
transmitter functions work up to
60 m (195 ft) away from the vehicle.
There are other conditions which
can affect the performance of the
transmitter. See Remote Keyless
Entry (RKE) System on page 2‑2.
With Remote Start (without
Remote Start Similar)
/(Remote Vehicle Start): For
vehicles with this feature, press
/
to start the engine from outside the
vehicle using the RKE transmitter.
See Remote Vehicle Start on
page 2‑5 for additional information.
Q(Lock):Press to lock all the
doors.
If enabled through the Driver
Information Center (DIC), the turn
signal lamps flash once to indicate
locking has occurred. If enabled
through the DIC, the horn chirps when
Qis pressed again within
three seconds. See Vehicle
Personalization (With DIC Buttons)
on page 5‑48 for additional
information.
Pressing
Qarms the content
theft‐deterrent system. See
Anti-theft Alarm System on
page 2‑11.
K(Unlock): Press once to unlock
only the driver door. If
Kis pressed
again within three seconds, all
remaining doors unlock. The interior
lamps may come on and stay on for
20 seconds or until the ignition is
turned on.
If enabled through the DIC, the turn
signal lamps flash twice to indicate
unlocking has occurred. See Vehicle
Personalization (With DIC Buttons)
on page 5‑48. If enabled through the
DIC, the exterior lights may turn on.
See “Approach Lighting” under
Vehicle Personalization (With DIC
Buttons) on page 5‑48.

Black plate (6,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
2-6 Keys, Doors, and Windows
When the vehicle starts, the
parking lamps will turn on and
remain on while the vehicle is
running. The doors will be
locked and the climate control
system may come on.
The engine will continue to run
for 10 minutes. Repeat the steps
for a 10-minute time extension.
Remote start can be extended
only once.
After entering the vehicle during a
remote start, insert and turn the key
to ON/RUN to drive the vehicle.
To cancel a remote start:
.Aim the RKE transmitter at the
vehicle and press and hold
/
until the parking lamps turn off.
.Turn on the hazard warning
flashers.
.Turn the ignition on and then
back off. The vehicle can be remote started
two separate times between driving
sequences. The engine will run for
10 minutes after each remote start.
Or, you can extend the engine run
time by another 10 minutes within
the first 10 minute remote start time
frame, and before the engine stops.
For example, if
Qand then/are
pressed again after the vehicle
has been running for five minutes,
10 minutes are added, allowing the
engine to run for 15 minutes.
The additional 10 minutes are
considered a second remote vehicle
start.
Once two remote starts, or a single
remote start with one time extension
has been done, the vehicle must be
started with the key. After the key is
removed from the ignition, the
vehicle can be remote started again. The vehicle cannot be remote
started if the key is in the ignition,
the hood is not closed, or if there
is an emission control system
malfunction and the check engine
light is on.
Also, the engine will turn off during a
remote vehicle start if the coolant
temperature gets too high or if the
oil pressure gets low.
Remote Start Ready
If the vehicle does not have the
remote vehicle start feature, it may
have the remote start ready feature.
This feature allows your dealer to
add the manufacturer's remote
vehicle start feature.
See your dealer to add the
manufacturer's remote vehicle start
feature to the vehicle.

Black plate (13,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Keys, Doors, and Windows 2-13
Immobilizer Operation
This vehicle has PASS-Key®III+
(Personalized Automotive Security
System) theft-deterrent system.
PASS-Key III+ is a passive
theft-deterrent system.
The system is automatically armed
when the key is removed from the
ignition.
The system is automatically
disarmed when the key is turned
to ON/RUN, ACC/ACCESSORY,
or START from the LOCK/OFF
position.
You do not have to manually arm or
disarm the system.
The security light will come on if
there is a problem with arming or
disarming the theft-deterrent
system.
When the PASS-Key III+ system
senses that someone is using the
wrong key, it prevents the vehicle
from starting. Anyone using a
trial-and-error method to start the vehicle will be discouraged because
of the high number of electrical key
codes.
If the engine does not start and the
security light on the instrument
panel cluster comes on when trying
to start the vehicle, there may be a
problem with the theft-deterrent
system. Turn the ignition off and try
again.
If the engine still does not start, and
the key appears to be undamaged,
try another ignition key. At this time,
you may also want to check the
fuse. See
Fuses and Circuit
Breakers on page 10‑44. If the
engine still does not start with the
other key, the vehicle needs service.
If the vehicle does start, the first key
may be faulty. See your dealer who
can service the PASS-Key III+ to
have a new key made.
It is possible for the PASS-Key III+
decoder to learn the transponder
value of a new or replacement key.
Up to 10 keys may be programmed for the vehicle. The following
procedure is for programming
additional keys only. If all the
currently programmed keys are lost
or do not operate, you must see
your dealer or a locksmith who can
service PASS-Key III+ to have keys
made and programmed to the
system.
See your dealer or a locksmith who
can service PASS-Key III+ to get a
new key blank cut exactly as the
ignition key that operates the
system.
To program the new additional key:
1. Verify that the new key has
a
1stamped on it.
2. Insert the original, already programmed key in the ignition
and start the engine. If the
engine will not start, see your
dealer for service.
3. After the engine has started, turn the key to LOCK/OFF, and
remove the key.

Black plate (11,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Instruments and Controls 5-11
Ashtrays
The vehicle may have a front
ashtray located near the center of
the instrument panel. Pull on the
door to open it. The ashtray may
have a cigarette lighter.
Notice:If papers, pins, or other
flammable items are put in the
ashtray, hot cigarettes or other
smoking materials could ignite
them and possibly damage the
vehicle. Never put flammable
items in the ashtray.
To remove the ashtray, open the
door and pull the ashtray bin toward
you. To replace the ashtray, insert
the ashtray bin inside the ashtray
door and press down until it
engages.
Warning Lights,
Gauges, and
Indicators
Warning lights and gauges can
signal that something is wrong
before it becomes serious enough
to cause an expensive repair or
replacement. Paying attention to the
warning lights and gauges could
prevent injury.
Warning lights come on when there
could be a problem with a vehicle
function. Some warning lights come
on briefly when the engine is started
to indicate they are working. Gauges can indicate when there
could be a problem with a vehicle
function. Often gauges and warning
lights work together to indicate a
problem with the vehicle.
When one of the warning lights
comes on and stays on while
driving, or when one of the gauges
shows there may be a problem,
check the section that explains what
to do. Follow this manual's advice.
Waiting to do repairs can be costly
and even dangerous.

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 (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 (24,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
5-24 Instruments and Controls
The following may correct an
emission system malfunction:
.Check that the fuel cap is fully
installed. SeeFilling the Tank on
page 9‑72. The diagnostic
system can determine if the
fuel cap has been left off or
improperly installed. A loose or
missing fuel cap allows fuel to
evaporate into the atmosphere.
A few driving trips with the cap
properly installed should turn the
light off.
.Check that good quality fuel is
used. Poor fuel quality causes
the engine not to run as
efficiently as designed and may
cause stalling after start-up,
stalling when the vehicle is
changed into gear, misfiring,
hesitation on acceleration,
or stumbling on acceleration.
These conditions might go away
once the engine is warmed up. If one or more of these conditions
occurs, change the fuel brand used.
It will require at least one full tank of
the proper fuel to turn the light off.
See
Recommended Fuel on
page 9‑68.
If none of the above have made
the light turn off, your dealer can
check the vehicle. The dealer has
the proper test equipment and
diagnostic tools to fix any
mechanical or electrical problems
that might have developed.Emissions Inspection and
Maintenance Programs
Some local governments may have
programs to inspect the on-vehicle
emission control equipment. For
the inspection, the emission system
test equipment is connected
to the vehicle’s Data Link
Connector (DLC).
The DLC is under the instrument
panel to the left of the steering
wheel. See your dealer if assistance
is needed.
The vehicle may not pass
inspection if:
.The malfunction indicator lamp is
on with the engine running, or if
the light does not come on when
the ignition is turned to ON/RUN
while the engine is off. See
your dealer for assistance in
verifying proper operation of the
malfunction indicator lamp.
.The OBD II (On-Board
Diagnostics) system
determines that critical
emission control systems have
not been completely diagnosed.