Owner’s Manual

Black plate (23,1)
GMC Yukon/Yukon XL Owner Manual - 2011
Vehicle Care 10-23
.
Idles for long periods in traffic.
.
Tows a trailer. See Trailer
Towing on page 9‑79.
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 gauge
is no longer in the overheat zone
or an overheat warning no longer
displays, the vehicle can be driven.
Continue to drive the vehicle slowly
for about 10 minutes. Keep a safe
vehicle distance from the vehicle in
front. 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”
later in this section.
Overheated Engine
Protection
Operating Mode
If an overheated engine condition
exists and the ENGINE POWER IS
REDUCED message is displayed,
an overheat protection mode which
alternates firing groups of cylinders
helps prevent engine damage. In
this mode, a loss in power and
engine performance will be noticed.
This operating mode allows the
vehicle to be driven to a safe place
in an emergency. Driving extended
distances 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, change the oil and
reset the oil life system. See
Engine Oil on page 10‑7.
Engine Fan
If the vehicle has a clutched
engine cooling fan, when the clutch
is engaged, the fan spins faster to
provide more air to cool the engine.
In most everyday driving conditions,
the fan is spinning slower and
the clutch is not fully engaged.