2008 CADILLAC DTS engine light

Engine Coolant Temperature Gage
This gage shows the
engine coolant
temperature.
It indicates when the engine has warmed up and if
the cooling system is operating properly. If the gage
pointer moves into the shaded area, the engine coolant
is too hot and the engine coolant temperature warning
light will come on. SeeEngine Overheating on
page 5-27for more information.
Tire Pressure Light
This light comes on briey
when the engine is started.
This light will also come on when one or more of your
tires are signicantly underinated.
A tire pressure message in the Driver Information
Center (DIC), may accompany the light. SeeDIC
Warnings and Messages on page 3-75for more
information.
Stop and check your tires as soon as it is safe to
do so. If underinated, inate to the proper pressure.
SeeTires on page 5-52for more information.
If a problem is detected with the Tire Pressure Monitor
System, this light will ash for approximately 60 seconds
and then stay on solid for the remainder of the ignition
cycle. SeeTire Pressure Monitor System on page 5-63
for more information.
3-64

Malfunction Indicator Lamp
Check Engine Light
A computer system called OBD II (On-Board
Diagnostics-Second Generation) monitors operation of
the fuel, ignition, and emission control systems. It makes
sure that emissions are at acceptable levels for the life of
the vehicle, helping to produce a cleaner environment.
The check engine light
comes on to indicate
that there is an OBD II
problem and service
is required.
Malfunctions often are indicated by the system before
any problem is apparent. This can prevent more serious
damage to your vehicle. This system is also designed
to assist your service technician in correctly diagnosing
any malfunction.
Notice:If you keep driving your vehicle with this
light on, after a while, the emission controls
might not work as well, your vehicle’s 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 your warranty.Notice:Modications made to the engine,
transmission, exhaust, intake, or fuel system of
your vehicle or the replacement of the original tires
with other than those of the same Tire Performance
Criteria (TPC) can affect your vehicle’s emission
controls and can cause this light to come on.
Modications to these systems could lead to costly
repairs not covered by your warranty. This could
also result in a failure to pass a required Emission
Inspection/Maintenance test. SeeAccessories
and Modifications on page 5-3.
This light comes on, as a check to show it is working,
when the ignition is turned ON/RUN but the engine is not
running. If the light does not come on, have it repaired.
This light also comes on during a malfunction in
one of two ways:
Light Flashing— A misre condition has been
detected. A misre increases vehicle emissions and
could damage the emission control system on your
vehicle. Diagnosis and service might be required.
Light On Steady— An emission control system
malfunction has been detected on your vehicle.
Diagnosis and service might be required.
3-65

If the Light is Flashing
The following can prevent more serious damage to your
vehicle:
Reduce vehicle speed.
Avoid hard accelerations.
Avoid steep uphill grades.
If you are towing a trailer, reduce the amount of
cargo being hauled as soon as it is possible.
If the light stops ashing and remains on steady,
see “If the Light Is On Steady” following.
If the light continues to ash, when it is safe to do so,
stop the vehicle. Find a safe place to park the vehicle.
Turn the ignition off, wait at least 10 seconds, and restart
the engine. If the light remains on steady, see “If the
Light Is On Steady” following. If the light is still ashing,
follow the previous steps and see your dealer/retailer
for service as soon as possible.
If the Light Is On Steady
You might be able to correct the emission system
malfunction by considering the following:
Did you recently put fuel into your vehicle?
If so, reinstall the fuel cap, making sure to fully
install the cap. SeeFilling the Tank on page 5-8.
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.
Did you just drive through a deep puddle of water?
If so, your vehicle’s electrical system might be wet. The
condition is usually corrected when the electrical system
dries out. A few driving trips should turn the light off.
Have you recently changed brands of fuel?
If so, be sure to fuel your vehicle with quality fuel. See
Gasoline Octane on page 5-5. Poor fuel quality causes
the engine not to run as efficiently as designed. You
might notice this as stalling after start-up, stalling when
you put the vehicle into gear, misring, hesitation on
acceleration, or stumbling on acceleration — these
conditions might go away once the engine is warmed up.
This will be detected by the system and cause the light to
turn on.
If you experience one or more of these conditions,
change the fuel brand you use. It will require at least
one full tank of the proper fuel to turn the light off.
If none of the above steps have made the light turn off,
your dealer/retailer can check the vehicle. Your
dealer/retailer has the proper test equipment and
diagnostic tools to x any mechanical or electrical
problems that might have developed.
3-66

Emissions Inspection and
Maintenance Programs
Some state/provincial and local governments have
or might begin programs to inspect the emission
control equipment on your vehicle. Failure to pass this
inspection could prevent you from getting a vehicle
registration.
Here are some things you need to know to help your
vehicle pass an inspection:
Your vehicle will not pass this inspection if the check
engine light is on or not working properly.
Your vehicle will not pass this inspection if the OBD
(on-board diagnostic) system determines that critical
emission control systems have not been completely
diagnosed by the system. The vehicle would be
considered not ready for inspection. This can happen
if you have recently replaced the battery or if the battery
has run down. The diagnostic system is designed to
evaluate critical emission control systems during normal
driving. This can take several days of routine driving.
If you have done this and your vehicle still does not pass
the inspection for lack of OBD system readiness, your
dealer/retailer can prepare the vehicle for inspection.
Oil Pressure Light
{CAUTION:
Do not keep driving if the oil pressure is low.
If you do, your engine can become so hot that
it catches re. You or others could be burned.
Check your oil as soon as possible and have
your vehicle serviced.
Notice:Lack of proper engine oil maintenance may
damage the engine. The repairs would not be covered
by your warranty. Always follow the maintenance
schedule in this manual for changing engine oil.
This light will come on
briey when you start your
engine as a check to be
sure it works. If it does
not, have your vehicle
serviced.
If the light comes on and stays on, it means that oil is not
owing through your engine properly. You could be low
on oil and you might have some other system problem.
3-67

Highbeam On Light
This light comes on when
the high-beam headlamps
are in use.
SeeHeadlamp High/Low-Beam Changer on page 3-9
for more information.
Fuel Gage
The fuel gage shows
approximately how
much fuel is in the tank.
It works only when
the engine is on.If the fuel supply gets low, the FUEL LEVEL LOW
message will appear in the Driver Information Center
and a single chime will sound. SeeDIC Warnings
and Messages on page 3-75for more information.
Here are a few concerns some owners have had about
the fuel gage. All of these situations are normal and
do not indicate that anything is wrong with the fuel gage:
At the gas station the gas pump shuts off before
the gage reads full.
The gage may change when you turn, stop quickly
or accelerate quickly.
It takes a little more or less fuel to ll the tank than
the gage indicated. For example, the gage may
have indicated that the tank was half full, but
it actually took a little more or less than half the
tank’s capacity to ll the tank.
3-69

DIC Warnings and Messages
These messages appear if there is a problem detected
in one of your vehicle’s systems.
You must acknowledge a message to clear it from the
screen for further use. To clear a message, press
the set/reset button.
Be sure to take any message that appears on the
screen seriously and remember that clearing the
message will only make the message disappear,
not the problem.
AUTOMATIC LIGHT CONTROL OFF
This message displays when the automatic headlamps
are turned off. SeeExterior Lamps on page 3-32for
more information.
AUTOMATIC LIGHT CONTROL ON
This message displays when the automatic headlamps
are turned on. SeeExterior Lamps on page 3-32for
more information.
BATTERY SAVER ACTIVE
This message displays when the system detects that
the battery voltage is dropping beyond a reasonable
level. The battery saver system starts reducing certain
features of the vehicle that you may be able to notice.At the point that the features are disabled, this message
is displayed. It means that the vehicle is trying to
save the charge in the battery.
Turn off all unnecessary accessories to allow the battery
to recharge.
The normal battery voltage range is 11.5 to 15.5 volts.
You can monitor battery voltage on the Driver Information
Center (DIC) by pressing the trip/fuel button until
BATTERY VOLTAGE is displayed.
CHANGE ENGINE OIL SOON
This message displays when service is required for your
vehicle. See your dealer/retailer. SeeEngine Oil on
page 5-15andScheduled Maintenance on page 6-4for
more information.
When you reset the CHANGE ENGINE OIL SOON
message by clearing it from the display, you still must
reset the engine oil life system separately. For more
information on resetting the engine oil life system, see
Engine Oil Life System on page 5-18.
CHECK TIRE PRESSURE
This message displays when the pressure in one or
more of the vehicle’s tires needs to be checked. This
message also displays LEFT FRONT, RIGHT FRONT,
LEFT REAR, or RIGHT REAR to indicate which tire
needs to be checked. You can receive more
than one tire pressure message at a time.
3-75

ENGINE HOT – A/C (Air
Conditioning) OFF
This message displays when the engine coolant
becomes hotter than the normal operating temperature.
SeeEngine Coolant Temperature Gage on page 3-64.
To avoid added strain on a hot engine, the air
conditioning compressor automatically turns off. When
the coolant temperature returns to normal, the air
conditioning compressor turns back on. You can
continue to drive your vehicle.
If this message continues to appear, have the system
repaired by your dealer/retailer as soon as possible
to avoid damage to the engine.
ENGINE OVERHEATED IDLE ENGINE
Notice:If you drive your vehicle while the engine
is overheating, severe engine damage may occur.
If an overheat warning appears on the instrument
panel cluster and/or DIC, stop the vehicle as soon
as possible. Do not increase the engine speed
above normal idling speed. SeeEngine Overheating
on page 5-27for more information.
This message displays when the engine coolant
temperature is too hot. Stop and allow the vehicle
to idle until it cools down. SeeEngine Coolant
Temperature Warning Light on page 3-63.SeeOverheated Engine Protection Operating Mode on
page 5-29for information on driving to a safe place
in an emergency.
ENGINE OVERHEATED STOP ENGINE
Notice:If you drive your vehicle while the engine
is overheating, severe engine damage may occur.
If an overheat warning appears on the instrument
panel cluster and/or DIC, stop the vehicle as soon as
possible. SeeEngine Overheating on page 5-27
for more information.
This message displays when the engine has overheated.
Immediately look for a safe place to pull your vehicle
over and turn the engine off right away to avoid severe
engine damage. SeeEngine Overheating on page 5-27
andOverheated Engine Protection Operating Mode
on page 5-29. A chime also sounds when this message
is displayed.
ENGINE POWER REDUCED
This message displays when the engine power is
being reduced to protect the engine from damage.
There could be several malfunctions that might cause
this message. 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.
3-77

NO CRUISE BRAKING GAS PEDAL
APPLIED
This message displays when the Adaptive Cruise
Control (ACC) is engaged and you are pressing the
accelerator pedal enough to disable ACC automatic
braking. SeeAdaptive Cruise Control on page 3-19for
more information.
OIL PRESSURE LOW STOP ENGINE
Notice:If you drive your vehicle while the engine
oil pressure is low, severe engine damage may
occur. If a low oil pressure warning appears on
the instrument panel cluster and/or DIC, stop the
vehicle as soon as possible. Do not drive the vehicle
until the cause of the low oil pressure is corrected.
SeeEngine Oil on page 5-15for more information.
This message displays when the vehicle’s engine
oil pressure is low. The oil pressure light also appears
on the instrument panel cluster. SeeOil Pressure
Light on page 3-67.
A multiple chime sounds when this message is
displayed. SeeEngine Oil on page 5-15for more
information.
Stop the vehicle immediately, as engine damage can
result from driving a vehicle with low oil pressure.
Have the vehicle serviced by your dealer/retailer as
soon as possible when this message is displayed.
PARKING ASSIST OFF
If your vehicle has the Ultrasonic Front and Rear
Parking Assist (UFRPA) system, after the vehicle is
shifted out of PARK (P), this message displays to remind
the driver that the UFRPA system has been turned
off. Press the set/reset button to acknowledge this
message and clear it from the DIC display. To turn
the UFRPA system back on, see “PARKING ASSIST”
underDIC Operation and Displays on page 3-70.
SeeUltrasonic Front and Rear Parking Assist (UFRPA)
on page 2-40for more information.
PASSENGER DOOR OPEN
This symbol appears
with this message.
This message displays when the passenger side front
door is not closed completely. Make sure that the door
is closed completely.
3-80