National Instruments 372139B-01 Automobile User Manual


 
Chapter 5 Automotive Diagnostic Command Set API for LabVIEW
© National Instruments Corporation 5-133 Automotive Diagnostic Command Set User Manual
OBD Request Powertrain Freeze Frame Data.vi
Purpose
Executes the OBD Request Powertrain Freeze Frame Data service. Reads an ECU data record
stored while a Diagnostic Trouble Code occurred.
Format
Input
diag ref in specifies the diagnostic session handle, obtained from Open
Diagnostic.vi and wired through subsequent diagnostic VIs. Normally, it is
not necessary to manually manipulate the elements of this cluster.
PID defines the parameter identifier of the data to be read. The SAE J1979
standard defines the values.
# frame is the number of the freeze frame from which the data are to be
retrieved.
error in is a cluster that describes error conditions occurring before the VI
executes. If an error has already occurred, the VI returns the value of the
error in cluster to error out.
status is TRUE if an error occurred. This VI is not executed when
status is TRUE.
code is the error code number identifying an error. A value of 0
means success. A negative value means error: the VI did not
execute the intended operation. A positive value means warning:
the VI executed intended operation, but an informational warning
is returned. For a description of the code, wire the error cluster to
a LabVIEW error-handling VI, such as the Simple Error
Handler.
source identifies the VI where the error occurred.