Ford NEW GENERATION STAR TESTER, Introduction Manual

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6-10 NGS-Generic OBD II
LESSON 6
NOTES
Freeze frame is a “snapshot” of operation conditions at the
time a MIL illuminating DTC occurs.
Freeze frame information is certain parameter identification
data (PID) at the time of the DTC. The data appearing in these
critical PlDs is locked into the freeze frame data memory
location.
The critical PlDs, their acronyms, descriptions and units of
measure are shown in the chart.
Freeze frame data is reached from the generic OBD II
functions menu.
Freeze frame data appearing on the NGS screen is for the
first detected emission related concern. That means that if
more than one emission related concern is encountered, the
first one detected will have freeze frame data available.
The exceptions to this are the DTCs for adaptive fuel at limit
(P1130 and P1150) and the misfire DTCs(P0300 through
P0308). These eleven DTCs have priority access to the
freeze frame storage area.
For example, the PCM detects a misfire or adaptive fuel
concern after another MIL level DTC has placed data in the
freeze frame memory location. The data for the misfire or
adaptive fuel concern always overwrites the data for the lower
priority DTC.
The freeze frame memory location is then locked to prevent
overwriting of the misfire or adaptive fuel information.