Cadillac 2005 CTS - Manual (Page 171)

Tire Pressure Light
This light will come on
if the system detects
low tire pressure.
This light will also come on for a bulb check when
the vehicle is started.
See Tire Pressure Monitor System (CTS-V) on
page 5-65 for more information.
For more information on the proper tire pressure,
see
Loading Your Vehicle on page 4-33. For more
information on your tires, see Tires on page 5-54.
Malfunction Indicator Lamp
Check Engine Light
Your vehicle is equipped
with a computer which
monitors operation of the
fuel, ignition, and emission
control systems.
This system is called OBD II (On-Board
Diagnostics-Second Generation) and is intended to
assure that emissions are at acceptable levels for the
life of the vehicle, helping to produce a cleaner
environment. The check engine light comes on to
indicate that there is a problem and service is required.
Malfunctions often will be indicated by the system
before any problem is apparent. This may prevent more
serious damage to your vehicle. This system is also
designed to assist your service technician in correctly
diagnosing any malfunction.
Notice: If you keep driving your vehicle with this
light on, after awhile, your emission controls may not
work as well, your fuel economy may not be as good,
and your engine may not run as smoothly. This could
lead to costly repairs that may not be covered by
your warranty.
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