Cadillac XT4 Owner Manual (GMNA-Localizing-Europe-16412942) - 2023 -
CRC - 5/25/22
98
Instruments and Controls
Malfunctions are often indicated by the
system before any problem is noticeable.
Being aware of the light and seeking service
promptly when it comes on may prevent
damage.
Caution
If the vehicle is driven continually with
this light on, the emission control system
may not work as well, the fuel economy
may be lower, and the vehicle may not
run smoothly. This could lead to costly
repairs that might not be covered by the
vehicle warranty.
Caution
Modifications to the engine, transmission,
exhaust, intake, or fuel system, or the
use of replacement tyres that do not
meet the original tyre specifications, can
cause this light to come on. This could
lead to costly repairs not covered by the
vehicle warranty. This could also affect
the vehicle's ability to pass an Emissions
Inspection/Maintenance test. See
.
When the light is on, a malfunction has
been detected. Diagnosis and service may be
required.
Poor fuel quality can cause inefficient engine
operation and poor driveability, which may
go away once the engine is warmed up.
If this occurs, change the fuel brand. It may
require at least one full tank of the proper
fuel to turn the light off. See
.
If the light remains on, see your retailer.
Emissions Inspection and Maintenance
Programs
If the vehicle requires an Emissions
Inspection/Maintenance test, the test
equipment will likely connect to the
vehicle's Data Link Connector (DLC).
The DLC is under the instrument panel to
the left of the steering wheel. Connecting
devices that are not used to perform an
Emissions Inspection/Maintenance test or to
service the vehicle may affect vehicle
operation. See
. See your dealer if assistance is
needed.
The vehicle may not pass inspection if:
.
The light is on when the engine is
running.
.
The light does not come on when the
ignition is in Service Mode.
.
Critical emission control systems have not
been completely diagnosed. If this
happens, the vehicle would not be ready
for inspection and might require
several days of routine driving before the
system is ready for inspection. This can
happen if the 12-volt battery has recently
been replaced or run down, or if the
vehicle has recently been serviced.
See your retailer if the vehicle will not pass
or cannot be made ready for the test.
Brake System Warning Light