2009 CADILLAC CTS heater

Engine Coolant
The cooling system in the vehicle for all engines and
the intercooler is lled with DEX-COOL®. This coolant is
designed to remain in the vehicle for ve years or
150,000 miles (240 000 km), whichever occurs rst.
The following explains the cooling system and how to
check and add coolant when it is low. If there is a
problem with engine overheating, seeEngine
Overheating on page 5-37.
What to Use
{CAUTION:
Adding only plain water to the cooling system can
be dangerous. Plain water, or some other liquid
such as alcohol, can boil before the proper coolant
mixture will. The vehicle’s coolant warning system
is set for the proper coolant mixture. With plain
water or the wrong mixture, the engine could get
too hot but you would not get the overheat
warning. The engine could catch re and you or
others could be burned. Use a 50/50 mixture of
clean, drinkable water and DEX-COOL
®coolant.Use a 50/50 mixture of clean, drinkable water and
DEX-COOL
®coolant. If using this mixture, nothing else
needs to be added. This mixture:
Gives freezing protection down to−34°F (−37°C),
outside temperature.
Gives boiling protection up to 265°F (129°C),
engine temperature.
Protects against rust and corrosion.
Will not damage aluminum parts.
Helps keep the proper engine temperature.
Notice:If an improper coolant mixture is used, the
engine could overheat and be badly damaged. The
repair cost would not be covered by the vehicle
warranty. Too much water in the mixture can freeze
and crack the engine, radiator, heater core, and
other parts.
Notice:If extra inhibitors and/or additives are used
in the vehicle’s cooling system, the vehicle could
be damaged. Use only the proper mixture of
the engine coolant listed in this manual for the
cooling system. SeeRecommended Fluids and
Lubricants on page 6-14for more information.
5-32

If No Steam Is Coming From The
Engine Compartment
If an engine overheat warning is displayed but no steam
can be seen or heard, the problem may not be too
serious. Sometimes the engine can get a little too hot
when the vehicle:
Climbs a long hill on a hot day.
Stops after high-speed driving.
Idles for long periods in traffic.
Tows a trailer.
If the overheat warning is displayed with no sign of
steam:
1. Turn the air conditioning off.
2. Turn the heater on to the highest temperature and
to the highest fan speed. Open the windows as
necessary.
3. In heavy traffic, let the engine idle in N (Neutral)
while stopped. If it is safe to do so, pull off the
road, shift to P (Park) or N (Neutral) and let
the engine idle.
If the temperature overheat gage is no longer in the
overheat zone or an overheat warning no longer
displays, the vehicle can be driven. Continue to drive
the vehicle slow for about 10 minutes. Keep a safe
vehicle distance from the car in front of you. If the
warning does not come back on, continue to drive
normally.If the warning continues, pull over, stop, and park the
vehicle right away.
If there is no sign of steam, idle the engine for
three minutes while parked. If the warning is still
displayed, turn off the engine until it cools down. Also,
see “Overheated Engine Protection Operating Mode”
next in this section.
Overheated Engine Protection
Operating Mode
This operating mode allows your vehicle to be driven
to a safe place in an emergency. Should a hot engine
condition exist, an overheat protection mode which
alternates ring groups of cylinders helps prevent engine
damage. In this mode, there is a loss in power and engine
performance. Driving extended miles (km) and/or towing
a trailer in the overheat protection mode should be
avoided.
Notice:After driving in the overheated engine
protection operating mode, to avoid engine damage,
allow the engine to cool before attempting any
repair. The engine oil will be severely degraded.
Repair the cause of coolant loss and change the oil.
SeeEngine Oil on page 5-18.
5-39

Mini-Fuses Usage
STR/WHL/
ILLUMSteering Wheel Illumination
TCM BATTTransmission Control Module
Battery
MAN SPD
SNSRManual Speed Sensor
WPR Windshield Wiper
ENG PUMP Engine Pump
J-Case Fuses Usage
ABS MTR ABS Motor
BLWR Blower
BRK VAC
PUMPBrake Vacuum Pump
FAN 1 Cooling Fan 1
FAN 2 Cooling Fan 2
REAR DEFOG Rear Defogger
SPARE Spare
EPB Electric Park Brake
J-Case Fuses Usage
SPARE Spare
STRTR Starter
SPARE Spare
WSW/HTR Windshield Washer Heater
Relays Usage
A/C CMPRSR
CLTCHAir Conditioning Compressor Clutch
DRL (W/O HID)
LO BEAM (HID)Daytime Running Lamps
(without High Intensity Discharge),
Low-Beam Headlamps
(High Intensity Discharge)
ENG PUMP Engine Pump
FAN S/P Cooling Fan Series/Parallel
FAN 1 Cooling Fan 1
FAN 2 Cooling Fan 2
HI BEAM High-Beam Headlamp
HORN Horn
IGN 1 Ignition 1
5-118

J-Case Fuses Usage
REAR DEFOG Rear Defogger
SPARE Spare
EPB Electric Park Brake
MRTD MR Ride/Suspension Control
STRTR Starter
SPARE Spare
WSW/HTR Windshield Washer Heater
Relays Usage
A/C CMPRSR
CLTCHAir Conditioning Compressor Clutch
LO BEAM Low Beam
INCL Intercooler Pump
FAN S/P Cooling Fan Series/Parallel
FAN 1 Cooling Fan 1
FAN 2 Cooling Fan 2
HI BEAM High-Beam Headlamp
HORN Horn
IGN 1 Ignition 1
LT DRL Left Daytime Running Lamps
Relays Usage
PWR/TRN Powertrain
REAR DEFOG Rear Defogger
SPARE Spare
STRTR Starter
WPR Windshield Wiper
WPR HI Windshield Wiper High Speed
DRL/WSWDaytime Running Lamps/Windshield
Washer Pump
FOG LAMP Fog Lamps
RT DRL Right Daytime Running Lamp
Circuit
BreakersUsage
HEAD LAMP
WASHHeadlamp Washer
Rear Compartment Fuse Block (CTS)
The rear compartment fuse block is located on top of
the battery, on the right side of the trunk. The battery
access door must be removed to access the fuse block.
5-122

Engine
Air Cleaner/Filter.........................................5-25
Check and Service Engine Soon Lamp...........3-43
Coolant......................................................5-32
Coolant Heater............................................2-35
Coolant Temperature Gage...........................3-42
Coolant Temperature Warning Light................3-41
Cover........................................................5-23
Drive Belt Routing.......................................6-17
Engine Compartment Overview......................5-14
Exhaust.....................................................2-50
Oil .............................................................5-18
Oil Life System...........................................5-21
Oil Pressure Gage.......................................3-47
Overheated Protection Operating Mode...........5-39
Overheating................................................5-37
Speed Limiter.............................................3-34
Starting......................................................2-33
Entry Lighting.................................................3-20
Event Data Recorders.....................................7-17
Extender, Safety Belt.......................................1-33
Exterior Lighting Battery Saver..........................3-20
F
Filter
Engine Air Cleaner......................................5-25
Finish Damage.............................................5-113
Flashers, Hazard Warning.................................. 3-6Flash-to-Pass................................................... 3-9
Flat Tire........................................................5-85
Flat Tire, Changing.........................................5-96
Flat Tire, Storing...........................................5-104
Fluid
Automatic Transmission................................5-29
Power Steering...........................................5-40
Windshield Washer......................................5-41
Fog Lamp
Fog ...........................................................3-19
Fog Lamp Light..............................................3-48
Folding Rear Seat...........................................1-13
Fuel............................................................... 5-5
Additives...................................................... 5-7
California Fuel.............................................. 5-7
Filling a Portable Fuel Container....................5-11
Filling the Tank............................................. 5-8
Fuels in Foreign Countries.............................. 5-8
Gage .........................................................3-49
Gasoline Octane........................................... 5-6
Gasoline Specications.................................. 5-6
Fuses
Fuses and Circuit Breakers.........................5-115
Rear Compartment Fuse Block..........5-122, 5-124
Underhood Fuse Block......................5-115, 5-119
Windshield Wiper.......................................5-115
5

G
Gage
Boost.........................................................3-50
Engine Coolant Temperature.........................3-42
Engine Oil Pressure.....................................3-47
Fuel..........................................................3-49
Speedometer..............................................3-33
Tachometer.................................................3-34
Garage Door Opener.......................................2-60
Gasoline
Octane........................................................ 5-6
Specications............................................... 5-6
Glove Box.....................................................2-64
GM Mobility Reimbursement Program.................. 7-7
H
Hazard Warning Flashers................................... 3-6
Head Restraints............................................... 1-2
Headlamp
Aiming .......................................................5-53
Headlamps....................................................3-17
Adaptive Forward Lighting System.................3-19
Bulb Replacement.......................................5-57Headlamps (cont.)
Daytime Running Lamp................................3-18
Flash-to-Pass............................................... 3-9
Front Turn Signal and Fog Lamps..................5-58
Halogen Bulbs............................................5-57
High Intensity Discharge (HID) Lighting...........5-57
High/Low Beam Changer................................ 3-8
On Reminder..............................................3-17
Washer......................................................3-13
Wiper Activated...........................................3-17
Heated Seats................................................... 1-7
Heater...........................................................3-24
Engine Coolant...........................................2-35
Highbeam On Light.........................................3-49
High-Speed Operation, Tires.............................5-70
Highway Hypnosis...........................................4-15
Hill and Mountain Roads..................................4-16
Hood
Checking Things Under................................5-12
Release.....................................................5-12
Horn ............................................................... 3-6
How to Wear Safety Belts Properly...................1-19
Hydraulic Clutch.............................................5-30
6