Cadillac XT4 2023 Owner's Manual page 128

Caution (Continued)
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 Accessories and
Modifications 0 327.
If the light is flashing : A
malfunction has been
detected that could damage
the emission control system
and increase vehicle
emissions. Diagnosis and
service may be required.
To help prevent damage,
reduce vehicle speed and
avoid hard accelerations and
uphill grades. If towing a
trailer, reduce the amount of
cargo being hauled as soon as
possible.
If the light continues to flash,
find a safe place to park. Turn
the vehicle off and wait at
least 10 seconds before
restarting the engine. If the
light is still flashing, follow the
previous guidelines and see
your dealer for service as
soon as possible.
If the light is on steady : A
malfunction has been
detected. Diagnosis and
service may be required.
Check the following:
If fuel has been added to the
vehicle using the capless fuel
funnel adapter, make sure
that it has been removed.
See Filling the Tank with a
Portable Gas Can under
Filling the Tank 0 311. The
diagnostic system can
detect if the adapter has
been left installed in the
vehicle, allowing fuel to
evaporate into the
atmosphere. A few driving
trips with the adapter
removed may turn off the
light.
Instruments and Controls
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
Recommended Fuel 0 310.
If the light remains on, see
your dealer.
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).
127