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is to assist the service technician after a vehicle repair and after
clearing diagnostic information, by reporting test results after a
driving cycle.
a) If a test failed during the driving cycle, the DTC associated with
that test is reported. If the pending fault does not occur again
within 40 to 80 warm-up cycles, the fault is automatically
cleared from memory.
b) Test results reported by this service do not necessarily indicate
a faulty component or system. If test results indicate another
failure after additional driving, then a DTC is set to indicate a
faulty component or system, and the MIL is illuminated.
Freeze Frame
In most cases the stored frame is the last DTC that occurred. Certain
DTCs, which have a greater impact on vehicle emission, have a
higher priority. In these cases, the top prioritized DTC is the one for
which the freeze frame records are retained. Freeze frame data
includes a
“snapshot” of critical parameter values at the time the
DTC is set.
Erase Codes
This option is used to clear all emission related diagnostic data such
as, DTCs, freeze frame data and manufacturer specific enhanced
data from the vehicle
’s ECM, and reset the I/M Readiness Monitor
Status for all vehicle monitors to Not Ready or Not Complete status.
A confirmation screen displays when the clear codes option is
selected to prevent accidental loss of data. Select
Yes
on the
confirmation screen to continue or
No
to exit.
I/M Readiness
This function is used to check the readiness of the monitoring system. It is an
excellent function to use prior to having a vehicle inspected for compliance to
a state emissions program. Selecting I/M Readiness opens a submenu with
two choices:
Since DTCs Cleared
– displays the status of monitors since the last time
