Black plate (9,1)Chevrolet Tahoe and GMC Yukon/Yukon Denali Hybrid - 2011
Vehicle Care 10-9
Drive Motor/Generator
Control Module (DMCM)
Coolant Surge Tank
Pressure Cap
SeeEngine Compartment Overview
on page 10‑4 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 also has 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. See “Engine Coolant” and
“Cooling System” in the owner
manual for more information.
When it is safe to lift the hood:
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
Black plate (12,1)Chevrolet Tahoe and GMC Yukon/Yukon Denali Hybrid - 2011
10-12 Vehicle Care
5. Add the pre‐mixed DEX‐COOL,available at your dealer, 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, the vehicle
may need service. See your
dealer.
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.
Power Steering Fluid
The vehicle has electric power
steering and does not use power
steering fluid.
Battery
This vehicle has a standard 12‐volt
battery and a high voltage hybrid
battery.
Refer to the replacement number on
the original battery label when a
new standard 12‐volt battery is
needed. Only a trained service technician
with the proper knowledge and tools
should inspect, test, or replace the
hybrid battery. See your dealer if the
hybrid battery needs service. The
dealer has information on how to
recycle the hybrid battery. There
is also information available at
http://www.recyclemybattery.com.
If an airbag inflates or the vehicle
has been in a crash, the vehicle's
sensing system might command the
automatic hybrid battery disconnect
to open. See
Replacing Airbag
System Parts After a Crash on
page 3‑2 for more information.
{DANGER
Battery posts, terminals, and
related accessories contain lead
and lead compounds, chemicals
known to the State of California to
cause cancer and reproductive
harm. Wash hands after handling.
