2010 GMC YUKON HYBRID low oil pressure

Engine Coolant Temperature Gage
United StatesCanada
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
United StatesCanada
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.
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A reading in the low pressure zone may be caused by
a dangerously low oil level or some other problem
causing low oil pressure. Check the oil as soon as
possible.
{WARNING:
Do not keep driving if the oil pressure is low.
The engine can become so hot that it catches fire.
Someone could be burned. Check the oil as soon
as possible and have the vehicle serviced.
Notice: Lack of proper engine oil maintenance can
damage the engine. The repairs would not be
covered by the vehicle warranty. Always follow the
maintenance schedule in this manual for changing
engine oil.
AUTO STOP
When the engine goes into Automatic Engine Stop,
the oil pressure gage drops to zero when the
tachometer is at the AUTO STOP position. This is
normal and oil pressure returns to the normal operating
range once the engine starts.
See Starting the Vehicle
on page 3‑3for more
information.
AUTO STOP displays in the Driver Information
Center (DIC) when the vehicle speed is zero.
See DIC Warnings and Messages
on page 4‑12for more information.
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Oil Pressure Light
{WARNING:
Do not keep driving if the oil pressure is low.
The engine can become so hot that it catches fire.
Someone could be burned. Check the oil as soon
as possible and have the vehicle serviced.
Notice: Lack of proper engine oil maintenance can
damage the engine. The repairs would not be
covered by the vehicle warranty. Always follow the
maintenance schedule in this manual for changing
engine oil.
This light comes on
briefly as a check it
works, when the ignition
is in ON/RUN. If it does
not, have the vehicle
serviced.
If the light comes on and stays on, it means that oil is
not flowing through the engine properly. The vehicle
could be low on oil and might have some other system
problem.
During an AUTO STOP there is zero oil pressure, but
this light will not come on.
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hood is closed, you should have the hood switch
serviced. Failure to service the hood switch properly
can result in an Auto Start condition.
Auto Stops will be disabled when this message is
displayed. If the vehicle is in auto stop mode when this
message appears, the engine will instantly start.
OIL PRESSURE LOW STOP ENGINE
If engine oil pressure is low, this message will be
displayed on the DIC. Stop the vehicle as soon as
safely possible and do not operate it until the cause of
the low oil pressure has been corrected. Check your oil
level as soon as possible and have your vehicle
serviced. See“Engine Oil”in the owner manual Index.
SERVICE 4 WHEEL DRIVE
This message may display if a problem occurs with the
four-wheel-drive system. If this message appears, stop
as soon as possible and turn off the vehicle. Make sure
the key is in the LOCK/OFF position for at least
one minute and then restart the vehicle and check for
the message on the DIC display. If the message is still
displayed or appears again when you begin driving,
the four-wheel-drive system needs service. See your
dealer/retailer.
SERVICE BATTERY CHARGING
SYSTEM
If the 12V battery system faults or fails this message will
appear on the DIC. The battery/charging system light
will appear in the instrument panel cluster. See “Battery
Warning Light” in the owner manual Index. Driving with
this message on could drain the battery. Have the
electrical system checked as soon as possible.
SERVICE BRAKE SYSTEM
This message will be displayed if there is a problem
with the brake system. You will still be able to brake, but
it will be noticeably more difficult. Pull off the road to a
safe location and have your vehicle towed to the
nearest dealer/retailer for service. See “Brakes,”
“Brake System Warning Light,” and“ABS Brake System
Warning Light” in the owner manual Index.
SERVICE HYBRID SYSTEM
If this message is displayed on the DIC, the vehicle may
continue to operate, but you need to have it serviced as
soon as possible.
SERVICE POWER STEERING
This message displays if a problem has been detected
with the electric power steering. Have your vehicle
serviced by your dealer/retailer immediately.
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A. See“Engine Air Cleaner/Filter” in the owner
manual.
B. Drive Motor/Generator Control Module (DMCM). See Drive Motor/Generator Control Module
(DMCM) Cooling System on page 6‑9.
C. Engine Oil Dipstick. See “Engine Oil”in the owner
manual.
D. Automatic Transmission Fluid Dipstick. See Automatic Transmission Fluid on page 6‑5.
E. Brake Fluid Reservoir. See Brakes on page 6‑13.
F. See “Underhood Fuse Block” in the owner manual.
G. See “Windshield Washer Fluid” in the owner
manual.
H. Hybrid Auxiliary Fuse Block. See Underhood Fuse
Block on page 6‑26.
I. DMCM Coolant Surge Tank Pressure Cap. See Drive Motor/Generator Control Module (DMCM)
Coolant Surge Tank Pressure Cap on page 6‑8.
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
When to Check and Change Automatic
Transmission Fluid
It is usually not necessary to check the transmission
fluid level. The only reason for fluid loss is a
transmission leak or overheating the transmission.
If you suspect a small leak, then use the following
checking procedures to check the fluid level. However,
if there is a large leak, then it may be necessary to have
the vehicle towed to a dealer/retailer service department
and have it repaired before driving the vehicle further.
Notice: Use of the incorrect automatic transmission
fluid may damage the vehicle, and the damages may
not be covered by the vehicle's warranty. Always
use the automatic transmission fluid listed in
Recommended Fluids and Lubricants on page 7‑2.
Change the fluid and filter at the intervals listed in the
Maintenance Schedule. See Scheduled Maintenance in
the owner manual. Be sure to use the transmission fluid
listed in Recommended Fluids and Lubricants
on
page 7‑2.
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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.
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