2010 GMC YUKON HYBRID engine coolant

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 fixed before you drive the
vehicle or run the engine.
How to Add Coolant to the DMCM
Coolant Surge Tank
If no problem has been found yet, check to see if
coolant is visible in the DMCM coolant surge tank.
If coolant is visible, add pre‐mixed DEX-COOL™
coolant, available at your dealer/retailer, at the DMCM
coolant surge tank, but be sure the DMCM cooling
system, including the DMCM coolant surge tank
pressure cap, is cool before you do it. Use the
procedure following.
6-10

{WARNING:
Steam and scalding liquids from a hot cooling
system can blow out and burn you badly. They are
under pressure, and if you turn the coolant surge
tank pressure cap—even a little —they can come
out at high speed. Never turn the cap when the
cooling system, including the coolant surge tank
pressure cap, is hot. Wait for the cooling system
and coolant surge tank pressure cap to cool if you
ever have to turn the pressure cap.
Notice: Using coolant other than a pre‐mixed
DEX-COOL, available at your dealer/retailer, may
damage your vehicle. Any repairs would not be
covered by your warranty. Always use a pre‐mixed
DEX-COOL (silicate-free) coolant in your vehicle.
{WARNING:
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 , the vehicle must be
serviced by your dealer and a special fill procedure
must be followed.
Notice:
Attempting to fill the DMCM cooling surge
tank yourself when the fluid 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.
6-11

Turn the DMCM coolant surge tank pressure cap
slowly counterclockwise (left) about one full turn.
Wait 30 seconds.
2. Then keep turning the DMCM coolant surge tankpressure 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.
6-12

Maintenance Schedule
At Least Once a Year
Tire Sealant and Compressor Kit
Check the sealant expiration date printed on the
instruction label of the Tire Sealant and Compressor Kit
at least once a year. See your dealer/retailer for a
replacement canister.
Recommended Fluids and
Lubricants
Fluids identified below are specific to the hybrid vehicle
and can be obtained from your dealer/retailer. See the
owner manual for the other fluids and lubricants
recommended for the vehicle.Usage Fluid/Lubricant
Drive Motor/Generator
Control Module
(DMCM) Cooling
System Always use the pre-mixed
50/50 mixture of de‐ionized water
and DEX-COOL®(silicate-free)
coolant available at your dealer/
retailer. See Drive Motor/Generator
Control Module (DMCM) Cooling
System on page 6‑9.
Engine Drive Belt Routing
7-2

A
Alternating CurrentPower Outlet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2
Antilock Brake System (ABS) Warning Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-7
Audio System(s) Navigation/Radio System . . . . . . . . . . . . . . . . . . . . . . . . . 4-14
Automatic Transmission, Fluid . . . . . . . . . . . . . . . . . . . . . . .6-5
B
Battery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-16
Belt Routing, Engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-2
Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-13 Regenerative Braking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-18
System Warning Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-6
Bulb Replacement Taillamps, Turn Signal, Stoplamps andBack-up Lamps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-24
C
Canadian Owners . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ii
Capacities and Specifications . . . . . . . . . . . . . . . . . . . . . . 6-57
Chains, Tire . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-34
Charging System Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-4
Climate Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-2
Compressor Kit, Tire Sealant . . . . . . . . . . . . . . . . 6-35, 6-45
Coolant
Engine Temperature Gage . . . . . . . . . . . . . . . . . . . . . . . . . 4-8
Coolant Surge Tank Pressure Cap, (DMCM) . . . . . . . . .6-8
Cooling System, (DMCM) . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-9
D
Drive Motor/Generator Control Module (DMCM) Coolant Surge Tank Pressure Cap . . . . . . . . . . . . . . . . .6-8
Drive Motor/Generator Control Module (DMCM) Cooling System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-9
Driver Information Center (DIC) . . . . . . . . . . . . . . . . . . . . 4-12
Warnings and Messages . . . . . . . . . . . . . . . . . . . . . . . . . 4-12
i - 1

E
EngineCompartment Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-4
Coolant Temperature Gage . . . . . . . . . . . . . . . . . . . . . . . . 4-8
Drive Belt Routing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-2
Engine Coolant Heater . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-17
F
Flat Tire . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-34
Fluid Power Steering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-13
Four-Wheel Drive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-10
Fuel Gage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-11
Fuel Economy Gage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-5
G
Gages Engine Coolant Temperature . . . . . . . . . . . . . . . . . . . . . . 4-8
Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-11
Fuel Economy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-5
Oil Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-8
Tachometer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4
H
High Voltage Devices and Wiring . . . . . . . . . . . . . . . . . . . .6-3
I
Inflation - Tire Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-28
Instrument Panel Cluster . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-3
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iii
J
Jump Starting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-18
L
LightsAntilock Brake System (ABS) Warning . . . . . . . . . . . . . 4-7
Brake System Warning . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-6
Charging System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4
Oil Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-10
StabiliTrak
®Indicator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-7
Lumbar Manual Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2
i - 2