Jeep Cherokee 2009 Operating Information Manual page 180

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 emis-
sions, engine, and automatic transmission control
systems. When these systems are operating prop-
erly, your vehicle will provide excellent perfor-
mance and fuel economy, as well as engine
emissions well within current government regula-
tions.
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. Although your vehicle will usually
be drivable and not need towing, see your autho-
rized dealer for service as soon as possible.
CAUTION!
• Prolonged driving with the MIL on could cause
further damage to the emission control sys-
tem. It could also affect fuel economy and
drivability. The vehicle must be serviced be-
fore 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 Message
If the vehicle diagnostic system determines that
the fuel filler cap is loose, improperly installed, or
damaged, a "gASCAP" message will display in
the instrument cluster. Tighten the gas cap until a
"clicking" sound is heard. This is an indication that
the gas cap is properly tightened. Press the trip
odometer RESET button to turn off the message. If
the problem persists, the message will appear the
next time the vehicle is started. This might indicate
a damaged cap. If the problem is detected twice
in a row, the system will turn on the MIL. Resolving
the problem will turn the MIL light off.
SERVICE INFORMATION
Mopar Fluids, Lubricants, and Parts are avail-
able from your local authorized dealer and will
help you keep your vehicle operating at its best.
Your authorized dealer also has the qualified
service personnel, special tools, and equipment
to perform all service operations in an expert
manner.
Failure to perform maintenance services at the
specified intervals as outlined in the Maintenance
Schedule may void provisions of your Vehicle
Warranty.
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