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 emission 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.
Onboard Diagnostic System (OBD II)
Cybersecurity
Your vehicle is required to have an Onboard Diagnostic
system (OBD II) and a connection port to allow access to
information related to the performance of your emissions
controls. Authorized service technicians may need to
344 MAINTAINING YOUR VEHICLE
access this information to assist with the diagnosis and
service of your vehicle and emissions system.
WARNING!
•ONLY an authorized service technician should con-
nect equipment to the OBD II connection port in
order to diagnose or service your vehicle.
• If unauthorized equipment is connected to the
OBD II connection port, such as a driver-behavior
tracking device, it may:
• Be possible that vehicle systems, including
safety related systems, could be impaired or a
loss of vehicle control could occur that may result
in an accident involving serious injury or death.
• Access, or allow others to access, information
stored in your vehicle systems, including per-
sonal information. For further information, refer to “Cybersecurity” in the
“Understanding Your Instrument Panel” section.
EMISSIONS INSPECTION AND MAINTENANCE
PROGRAMS
In some localities, it may be a legal requirement to pass
an inspection of your vehicle’s emissions control system.
Failure to pass could prevent vehicle registration.
For states that require an Inspection and Mainte-
nance (I/M), this check verifies the “Malfunction
Indicator Light (MIL)” is functioning and is not
on when the engine is running, and that the OBD II
system is ready for testing.
Normally, the OBD II system will be ready. The OBD II
system may notbe ready if your vehicle was recently
serviced, recently had a dead battery or a battery replace-
ment. If the OBD II system should be determined not
ready for the I/M test, your vehicle may fail the test.
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