monitors are constantly evaluating, they will be reported as “Ready” all of the
time. If testing of a particular supported non-continuous monitor has not been
completed, the monitor status will be reported as “Not Complete” or “Not
Ready.”
In order for the OBD monitor system to become ready, the vehicle should be
driven under a variety of normal operating conditions. These operating
conditions may include a mix of highway driving and stop and go, city type
driving, and at least one overnight-off period. For specific information on
getting your vehicle’s OBD monitor system ready, please consult your vehicle
owner’s manual.
2.6 OBD II Definitions
Powertrain Control Module (PCM) -- OBD II terminology for the on-board
computer that controls engine and drive train.
Malfunction Indicator Light (MIL) -- Malfunction Indicator Light (Service
Engine Soon, Check Engine) is a term used for the light on the instrument
panel. It is to alert the driver and/or the repair technician that there is a
problem with one or more of vehicle's systems and may cause emissions to
exceed federal standards. If the MIL illuminates with a steady light, it
indicates that a problem has been detected and the vehicle should be
serviced as soon as possible. Under certain conditions, the dashboard light
will blink or flash. This indicates a severe problem and flashing is intended to
discourage vehicle operation. The vehicle onboard diagnostic system cannot
turn the MIL off until the necessary repairs are completed or the condition no
longer exists.
DTC -- Diagnostic Trouble Codes (DTC) that identifies which section of the
emission control system has malfunctioned.
Enabling Criteria -- Also termed Enabling Conditions. They are the vehicle-
specific events or conditions that must occur within the engine before the
various monitors will set, or run. Some monitors require the vehicle to follow a
prescribed “drive cycle” routine as part of the enabling criteria. Drive cycles
vary among vehicles and for each monitor in any particular vehicle. Please
refer to the vehicle's factory service manual for specific enabling procedures.
OBD II Drive Cycle -- A specific mode of vehicle operation that provides
conditions required to set all the readiness monitors applicable to the vehicle
to the “ready” condition. The purpose of completing an OBD II drive cycle is to
To Next Page
Loading...
Need help?
General
