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 auto-
matic transmission control systems. When these sys-
tems are operating properly, your vehicle will provide
excellent performance and fuel economy, as well as
engine emissions well within current government regu-
lations.
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 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.
(Continued)
CAUTION! (Continued)
The vehicle must be serviced before any emis-
sions 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 emis-
sions controls. Authorized service technicians may need
to access this information to assist with the diagnosis
and service of your vehicle and emissions system.
WARNING!
• ONLY an authorized service technician should
connect equipment to the OBD II connection port
in order to diagnose or service your vehicle.
(Continued)
280 MAINTAINING YOUR VEHICLE
WARNING!(Continued)
•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 sys-
tem. Failure to pass could prevent vehicle registration. For states that require an Inspection and Main-
tenance (I/M), this check verifies the “Malfunc-
tion 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
replacement. If the OBD II system should be deter-
mined not ready for the I/M test, your vehicle may fail
the test.
Your vehicle has a simple ignition actuated test, which
you can use prior to going to the test station. To check
if your vehicle’s OBD II system is ready, you must do
the following:
1. Cycle the ignition switch to the ON position, but do not crank or start the engine.
7
MAINTAINING YOUR VEHICLE 281
