2012 CHEVROLET SUBURBAN check engine light

Black plate (7,1)Chevrolet Tahoe/Suburban Owner Manual - 2012
Keys, Doors, and Windows 2-7
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.
Door Locks
{WARNING
Unlocked doors can be
dangerous.
.Passengers, especially
children, can easily open
the doors and fall out of a
moving vehicle. When a door
is locked, the handle will not
open it. The chance of being
thrown out of the vehicle in
a crash is increased if the
doors are not locked. So,
all passengers should wear
safety belts properly and
the doors should be locked
whenever the vehicle is
driven.
.Young children who get into
unlocked vehicles may be
unable to get out. A child can
be overcome by extreme heat
and can suffer permanent(Continued)
WARNING (Continued)
injuries or even death from
heat stroke. Always lock the
vehicle whenever leaving it.
.Outsiders can easily enter
through an unlocked door
when you slow down or stop
the vehicle. Locking the doors
can help prevent this from
happening.
There are several ways to lock and
unlock the vehicle.
From outside, use the Remote
Keyless Entry (RKE) transmitter or
the key in the driver door.
From inside, use the power door
locks or manual door locks. To lock
or unlock the door with the manual
locks, push down or pull up on the
manual lock knob.

Black plate (15,1)Chevrolet Tahoe/Suburban Owner Manual - 2012
Keys, Doors, and Windows 2-15
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 10‑37. 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 (10,1)Chevrolet Tahoe/Suburban Owner Manual - 2012
5-10 Instruments and Controls
If equipment is connected using
more than 150 watts or a system
fault is detected, a protection circuit
shuts off the power supply and the
indicator light turns off. To reset the
circuit, unplug the item and plug
it back in or turn the Remote
Accessory Power (RAP) off and
then back on. SeeRetained
Accessory Power (RAP) on
page 9‑26
The power outlet is not designed for
and may not work properly, if the
following are plugged in:
.Equipment with high initial
peak wattage such as:
compressor-driven refrigerators
and electric power tools.
.Other equipment requiring
an extremely stable
power supply such as:
microcomputer-controlled
electric blankets, touch sensor
lamps, etc.
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 (16,1)Chevrolet Tahoe/Suburban Owner Manual - 2012
5-16 Instruments and Controls
This cycle may 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.
Passenger Safety Belt
Reminder Light
When the vehicle is started, this
light flashes and a chime may come
on to remind front passengers to
fasten their safety belt. Then the
light stays on solid until the belt is
buckled.
For more information see
Passenger Airbag Status Indicator
on page 5‑17.This cycle continues several times
if the front passenger remains or
becomes unbuckled while the
vehicle is moving.
If the front passenger safety belt is
buckled, neither the chime nor the
light comes on.
The front passenger safety belt
reminder 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
reminder 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), passenger
sensing system, the pretensioners,
the airbag modules, the wiring, and
the crash sensing and diagnosticmodule. For more information on the
airbag system, see
Airbag System
on page 3‑29.
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
(Continued)

Black plate (18,1)Chevrolet Tahoe/Suburban Owner Manual - 2012
5-18 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 5‑16 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 5‑35 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 9‑22 for more information.

Black plate (20,1)Chevrolet Tahoe/Suburban Owner Manual - 2012
5-20 Instruments and Controls
The following may correct an
emission system malfunction:
.Check that the fuel cap is
fully installed. SeeFilling the
Tank on page 9‑63. 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 9‑60.
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. The
vehicle would be considered not
ready for inspection. This can

Black plate (24,1)Chevrolet Tahoe/Suburban Owner Manual - 2012
5-24 Instruments and Controls
Engine Oil Pressure Light
{WARNING
Do not keep driving if the oil
pressure is low. The engine can
become so hot that it catches fire.
Someone could be burned. Check
the oil as soon as possible and
have the vehicle serviced.
Notice: Lack of proper engine oil
maintenance can damage the
engine. The repairs would not be
covered by the vehicle warranty.
Always follow the maintenance
schedule for changing engine oil.
This light comes on briefly while
starting the engine. If it does not,
have the vehicle serviced by your dealer. If the system is working
normally the indicator light then
goes off.
If the light comes on and stays on, it
means that oil is not flowing through
the engine properly. The vehicle
could be low on oil and it might
have some other system problem.
If the vehicle is a hybrid, see the
hybrid supplement for more
information.
Low Fuel Warning Light
This light, under the fuel gauge,
comes on briefly while the engine is
being started.
This light and a chime come on
when the fuel tank is low on fuel.
The Driver Information Center also
displays a FUEL LEVEL LOWmessage. See
Fuel System
Messages on page 5‑39 for more
information. When fuel is added this
light and message should go off.
If they do not, have the vehicle
serviced by your dealer.
Security Light
The security light should come on
briefly as the engine is started. If the
system is working normally, the
indicator light turns off. If it does not
come on, have the vehicle serviced
by your dealer.
If the light stays on and the engine
does not start, there could be a
problem with the theft-deterrent
system.

Black plate (39,1)Chevrolet Tahoe/Suburban Owner Manual - 2012
Instruments and Controls 5-39
Engine Power Messages
ENGINE POWER IS REDUCED
This message displays and a chime
sounds when the cooling system
temperature gets too hot and the
engine further enters the engine
coolant protection mode. See
Engine Overheating on page 10‑19
for further information.
This message also displays when
the engine power is reduced.
Reduced engine power can affect
the vehicle's ability to accelerate.
If this message is on, but there
is no reduction in performance,
proceed to your destination. The
performance may be reduced the
next time the vehicle is driven. The
vehicle may be driven at a reduced
speed while this message is on, but
acceleration and speed may be
reduced. Anytime this message
stays on, the vehicle should be
taken to your dealer for service as
soon as possible.
Fuel System Messages
FUEL LEVEL LOW
This message displays and a chime
sounds if the fuel level is low. Refuel
as soon as possible. SeeFuel
Gauge on page 5‑12 andFuel on
page 9‑60 for more information.
TIGHTEN GAS CAP
This message may display along
with the check engine light on the
instrument panel cluster if the fuel
cap is not tightened properly. See
Malfunction Indicator Lamp on
page 5‑18. Reinstall the fuel cap
fully. SeeFilling the Tank on
page 9‑63. 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 this light and message off.
Key and Lock Messages
REPLACE BATTERY IN
REMOTE KEY
This message displays if a Remote
Keyless Entry (RKE) transmitter
battery is low. The battery needs
to be replaced in the transmitter.
See “Battery Replacement” under
Remote Keyless Entry (RKE)
System Operation on page 2‑3.
Lamp Messages
TURN SIGNAL ON
This message displays and a chime
sounds if a turn signal is left on for
1.2 km (0.75 mile). Move the turn
signal/multifunction lever to the off
position.