Creator
OBDII/EOBD scanner
13
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
vehicle’s Owner’s Manual. 7
Freeze Frame Data -- When an emissions related
fault occurs, the OBD II system not only sets
a code but also records a snapshot of the
vehicle
operating
parameters
to
help
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 temperature, ignition timing advance,
or closed loop status.
