2009 GMC YUKON HYBRID engine coolant

Climate Controls..............................................3-2
Warning Lights, Gages, and Indicators..............3-3
Instrument Panel Cluster.................................3-3
Tachometer...................................................3-4
Charging System Light....................................3-4
Fuel Economy Gage.......................................3-5
Brake System Warning Light............................3-6
Antilock Brake System (ABS) Warning Light.......3-7
StabiliTrak
®Indicator Light...............................3-7Engine Coolant Temperature Gage...................3-8
Oil Pressure Gage..........................................3-8
Oil Pressure Light.........................................3-10
Fuel Gage...................................................3-11
Driver Information Center (DIC).......................3-12
DIC Warnings and Messages.........................3-12
Audio System(s).............................................3-14
Navigation/Radio System...............................3-14
Section 3 Instrument Panel
3-1

Engine Coolant Temperature Gage
This gage shows the engine coolant temperature.
It also provides an indicator of how hard the vehicle is
working. During a majority of the operation, the gage
reads 210° F (100° C) or less. If a load is being pulled
or going up hills, it is normal for the temperature to
fluctuate and go over the 235° F (113° C) mark.
However, if the gage reaches the 260° F (125° C) mark,
it indicates that the cooling system is working beyond
its capacity.
Oil Pressure Gage
The oil pressure gage shows the engine oil pressure
in psi (pounds per square inch) when the engine
is running. Canadian vehicles indicate pressure in
kPa (kilopascals).
Oil pressure should be 29 to 80 psi (200 to 550 kPa).
In certain situations, such as long extended idles on
hot days, it could read as low as 15 psi (105 kPa) and
still be considered normal. United States
CanadaUnited StatesCanada
3-8

Service............................................................5-2
Doing Your Own Service Work.........................5-2
Checking Things Under the Hood.....................5-3
High Voltage Devices and Wiring......................5-3
Engine Compartment Overview.........................5-4
Automatic Transmission Fluid...........................5-5
Drive Motor/Generator Control Module (DMCM)
Coolant Surge Tank Pressure Cap..................5-6
Drive Motor/Generator Control Module (DMCM)
Cooling System...........................................5-6
Power Steering Fluid.....................................5-11
Brakes........................................................5-11
Battery........................................................5-15
Jump Starting...............................................5-16
Bulb Replacement..........................................5-21
Taillamps, Turn Signal, Stoplamps and
Back-up Lamps.........................................5-21
Replacement Bulbs.......................................5-22Electrical System............................................5-22
Fuses and Circuit Breakers............................5-22
Underhood Fuse Block..................................5-22
Tires..............................................................5-24
Inflation - Tire Pressure.................................5-24
Tire Pressure Monitor Operation.....................5-25
Tire Inspection and Rotation...........................5-29
Tire Chains..................................................5-30
If a Tire Goes Flat........................................5-30
Tire Sealant and Compressor Kit
(Without Selector Switch)............................5-32
Tire Sealant and Compressor Kit
(With Selector Switch)................................5-42
Tire Sealant and Compressor Kit Storage.........5-50
Capacities and Specications..........................5-52
Section 5 Service and Appearance Care
5-1

A. See “Engine Air Cleaner/Filter” in the owner manual.
B. Drive Motor/Generator Control Module (DMCM).
SeeDrive Motor/Generator Control Module (DMCM)
Cooling System on page 5-6.
C. Engine Oil Dipstick. See “Engine Oil” in the owner
manual.
D. Automatic Transmission Fluid Dipstick. See
Automatic Transmission Fluid on page 5-5.
E. Brake Fluid Reservoir. SeeBrakes on page 5-11.
F. See “Underhood Fuse Block” in the owner manual.
G. See “Windshield Washer Fluid” in the owner
manual.
H. Hybrid Auxiliary Fuse Block. SeeUnderhood Fuse
Block on page 5-22.
I. DMCM Coolant Surge Tank Pressure Cap. See
Drive Motor/Generator Control Module (DMCM)
Coolant Surge Tank Pressure Cap on page 5-6.
J. See “Coolant Surge Tank Pressure Cap” in
the owner manual.
K. Engine Oil Fill Cap. See “Engine Oil” in the owner
manual.Automatic Transmission Fluid
For more information, see “Automatic Transmission
Fluid” in the owner manual Index.
Checking the Fluid Level
Your vehicle’s automatic transmission dipstick looks like
this. For more information on location, seeEngine
Compartment Overview on page 5-4.
5-5

Drive Motor/Generator Control
Module (DMCM) Coolant Surge Tank
Pressure Cap
SeeEngine Compartment
Overview on page 5-4
for more information
on location.
The Drive Motor/Generator Control Module (DMCM)
coolant surge tank pressure cap must be fully installed
on the hybrid coolant surge tank.
Notice:If the pressure cap is not tightly installed,
coolant loss and possible damage to the Drive
Motor/Generator Control Module (DMCM) may occur.
Be sure the cap is properly and tightly secured.
Drive Motor/Generator Control
Module (DMCM) Cooling System
In addition to the regular cooling system, the vehicle is
also equipped with a cooling system for the DMCM
system. This system is serviced differently than
the vehicle’s main cooling system. The DMCM cooling
system includes the DMCM coolant surge tank,
DMCM surge tank pressure cap, DMCM cooling pumps,
hybrid cooling radiator and the Drive Motor/Generator
Control Module (DMCM). The DMCM cooling system
uses a 50/50 pre-mixed DEX-COOL™ coolant and
deionized water available at your dealer/retailer.
See “Engine Coolant” and “Cooling System” in the
owner manual for more information.
5-6

When you decide it is safe to lift the hood, here is what
you will see:
A. Drive Motor/Generator Control Module (DMCM)
B. Engine Coolant Surge Tank Pressure Cap
C. DMCM Coolant Surge Tank/Engine Coolant
Surge Tank
D. DMCM Cooling Hoses (Out of View)
E. DMCM Coolant Tank Pressure Cap
If the coolant inside the DMCM coolant surge tank is
boiling, do not do anything else until it cools down.The coolant level should be at or above the FULL
COLD mark with the vehicle parked on a level surface.
If it is not, there might be a leak at the DMCM cooler
core, DMCM pressure cap, DMCM cooler hoses,
DMCM cooling pump or somewhere else in the DMCM
cooling system.
Notice:Running the engine when there is a leak in
the hybrid cooling system can cause the hybrid
cooling system to lose all coolant and can damage
the system. Get any leak xed before you drive
the vehicle or run the engine.
5-7

{CAUTION:
You can be burned if you spill coolant on hot
engine parts. Coolant contains ethylene glycol
and it will burn if the engine parts are hot enough.
Do not spill coolant on a hot engine.
If the DMCM coolant is empty, your vehicle must be
serviced by your dealer and a special fill procedure
must be followed.
Notice:Attempting to ll the DMCM cooling surge
tank yourself when the uid level is empty can
damage your vehicle. Your vehicle must be serviced.1. Park the vehicle on a level surface and turn the
vehicle off. Remove the DMCM coolant surge
tank pressure cap when the DMCM cooling system,
including the DMCM coolant surge tank pressure
cap and DMCM cooling hoses, are no longer hot.
Turn the DMCM coolant surge tank pressure cap
slowly counterclockwise (left) about one full turn.
Wait 30 seconds.
5-9

2. Then keep turning the DMCM coolant surge tank
pressure cap slowly, and remove it.
3. Add the pre-mixed DEX-COOL™, available at your
dealer/retailer, to the DMCM coolant surge tank
until the level reaches the FULL COLD mark.
4. Turn the ignition to ON/RUN without starting the
engine. The hybrid cooling pumps will run and
any trapped air will purge to the surge tank.5. Add the pre-mixed DEX-COOL™, available at your
dealer/retailer, until the coolant level is maintained
at the FULL COLD mark. This should take no
longer than two minutes of hybrid cooling pump
operation.
If the level cannot be kept at the FULL COLD
level, your vehicle may need service. See your
dealer/retailer.
6. Then replace the
DMCM coolant surge
tank pressure cap.
Be sure the pressure
cap is hand-tight
and fully seated.
Notice:Using tap water, cooling system sealers or
conditioners in an attempt to stop coolant leaks
can damage the DMCM and engine cooling systems.
Never use tap water, cooling system sealers or
conditioners in your cooling system.
5-10