Description: An orange indicator light
labeled CHECK ENGINE or SERVICE ENGINE SOON, it's also known as the
MIL (Malfunction Indicator Lamp) in technical jargon. The importance
and function of this light became more critical starting in 1996,
when the second generation of onboard diagnostics, known as OBDII,
became standard equipment on all makes and models of cars.
Purpose: Required by the Environmental
Protection Agency (EPA) for tighter emissions control, OBDII has the
ability to monitor a diverse range of engine-related functions and
record critical information. You can think of this information as
your car's electronic "vital signs." OBDII information has proven to
be so credible that it is now being used by some states as part of
their emissions testing programs. The SERVICE ENGINE SOON or CHECK
ENGINE LIGHT has several modes and can indicate a normally
functioning system, a system that requires prompt attention, and a
system that needs immediate attention.
Maintenance Tips/Suggestions: If your car's OBDII system is functioning
properly, the CHECK ENGINE or SERVICE ENGINE SOON light should flash
briefly when you turn your car's ignition key to the on position.
After the brief flash, the light should go out and remain off while
you are driving.
A glowing CHECK ENGINE or SERVICE ENGINE SOON light alerts you to
problems in your car's onboard diagnostic system that should be
checked out as soon as possible. There's no reason to panic and in
many cases, you won't notice any difference in vehicle performance.
First, check the gas cap to make sure it wasn't left loose after
refueling. Sometimes, this can trigger the light. Most
OBDII-equipped vehicles have a gas cap that simply snaps in place,
when turned to the right. Some early OBDII-equipped vehicles have
threaded caps. On these, just turn the cap to the right until it
begins to click. If the gas cap was loose, the light should go out
after a few short trips.
If the gas cap wasn't the problem and the
light remains on steady, have the system checked out as soon as
possible. A light that flashes requires more prompt attention,
indicating
a more severe condition that must be checked out immediately to
prevent damage to the catalytic converter. When you experience a flashing
light, minimize driving at high speeds or under heavy loads. When
scheduling service, make sure the shop that
diagnoses your car has technicians who are properly trained and
certified for OBDII diagnosis and repair.
