Chrysler 2009 300 - Owner Manual - Manual (Page 422)

ONBOARD DIAGNOSTIC SYSTEM — OBD II
Your vehicle is equipped with a sophisticated onboard
diagnostic system called OBD II. This system monitors
the performance of the emissions, engine, and automatic
transmission control systems. When these systems are
operating properly, your vehicle will provide excellent
performance and fuel economy, as well as engine emis-
sions well within current government regulations.
If any of these systems require service, the OBD II system
will turn on the Malfunction Indicator Light (MIL). It will
also store diagnostic codes and other information to
assist your service technician in making repairs. Al-
though your vehicle will usually be drivable and not
need towing, see your authorized dealer for service as
soon as possible.
CAUTION!
Prolonged driving with the MIL on could cause
further damage to the emissions control system. It
could also affect fuel economy and driveability. The
vehicle must be serviced before any emissions tests
can be performed.
If the MIL is flashing while the engine is running,
severe catalytic converter damage and power loss
will soon occur. Immediate service is required.
Loose Fuel Filler Cap
If the vehicle diagnostic system determines that the fuel
filler cap is loose, improperly installed, or damaged, a
“Check Gascap” message will display in the Electronic
Vehicle Information Center (EVIC) (if equipped). If this
occurs, tighten the fuel filler cap properly and press the
TRIP ODOMETER button to turn off the message. If the
problem continues, the message will appear the next time
the vehicle is started.
420 MAINTAINING YOUR VEHICLE