Cadillac 2011 CTS Coupe Owner's Manual page 347

If an engine overheat warning is
displayed but no steam can be seen
or heard, the problem may not be
too serious. Sometimes the engine
can get a little too hot when the
vehicle:
Climbs a long hill on a hot day.
Stops after high-speed driving.
Idles for long periods in traffic.
Tows a trailer.
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 slow
for about 10 minutes. Keep a safe
vehicle distance from the car in front
of you. 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 next in this
section.
This operating mode allows the
vehicle to be driven to a safe place
in an emergency. Should a hot
engine condition exist, an overheat
protection mode which alternates
firing groups of cylinders helps
prevent engine damage. In this
mode, there is a loss in power
and engine performance. Driving
extended distances and/or towing a
trailer in the overheat protection
mode should be avoided.
See
for the location of the
power steering fluid reservoir.