CODESCAN CS602 User’s Manual
monitor system ready, please consult your vehicle owner’s manual.
3.6 OBD II Definitions
(PCM)
-- OBD II terminology for the on-board
alfunction Indicator Light (MIL)
-- Malfunction Indicator Light (Service
TC
-- Diagnostic Trouble Codes (DTC) that identifies which section of the
nabling Criteria
-- Also termed Enabling Conditions. They are the
BD II Drive Cycle
-- A specific mode of vehicle operation that provides
reeze Frame Data
-- When an emissions related fault occurs, the OBD II system
Powertrain Control Module
computer that controls engine and drive train.
M
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.
D
emission control system has malfunctioned.
E
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.
O
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 force the
vehicle to run its onboard diagnostics. Some form of a drive cycle needs to be
performed after DTCs have been erased from the PCM’s memory or after the battery
has been disconnected. Running through a vehicle’s complete drive cycle will “set”
the readiness monitors so that future faults can be detected. Drive cycles vary
depending on the vehicle and the monitor that needs to be reset. For vehicle specific
drive cycle, consult the service manual.
F
not only sets a code but also records a snapshot of the vehicle operating parameters
to help in identifying the problem. This set of values is referred to as Freeze Frame
Data and may include important engine parameters such as engine RPM, vehicle
speed, air flow, engine load, fuel pressure, fuel trim value, engine coolant
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