GMC 15919282 Automobile User Manual


 
This light comes on during a
malfunction in one of two ways:
Light Flashing: A misfire condition
has been detected. A misfire
increases vehicle emissions and
could damage the emission control
system on the vehicle. Diagnosis
and service might be required.
The following can prevent more
serious damage to the vehicle:
Reduce vehicle speed.
Avoid hard accelerations.
Avoid steep uphill grades.
If towing a trailer, reduce the
amount of cargo being hauled
as soon as it is possible.
If the light continues to flash,
when it is safe to do so, stop the
vehicle. Find a safe place to park the
vehicle. Turn the key off, wait at least
10 seconds, and restart the engine.
If the light is still flashing, follow the
previous steps and see your dealer/
retailer for service as soon as
possible.
Light On Steady: An emission
control system malfunction has been
detected on the vehicle. Diagnosis
and service might be required.
An emission system malfunction
might be corrected by checking the
following items:
Make sure the fuel cap is fully
installed. See Filling the Tank on
page 5-8. The diagnostic system
can determine if the fuel cap
has been left off or improperly
installed. A loose or missing
fuel cap allows fuel to evaporate
into the atmosphere. A few
driving trips with the cap properly
installed should turn the light off.
If the vehicle has been driven
through a deep puddle of water,
the vehicle’s electrical system
might be wet. The condition is
usually corrected when the
electrical system dries out.
A few driving trips should
turn the light off.
Make sure to fuel the vehicle
with quality fuel. Poor fuel quality
causes the engine not to run as
efficiently as designed and may
cause: stalling after start-up,
stalling when the vehicle is
changed into gear, misfiring,
hesitation on acceleration,
or stumbling on acceleration.
These conditions might go away
once the engine is warmed up.
If one or more of these conditions
occurs, change the fuel brand
used. It will require at least one
full tank of the proper fuel to turn
the light off.
See Gasoline Octane on
page 5-5.
If none of the above have made the
light turn off, your dealer/retailer can
check the vehicle. The dealer/retailer
has the proper test equipment and
diagnostic tools to fix any mechanical
or electrical problems that might
have developed.
Instrument Panel 3-43