Purpose

Executes the WWH-OBD ReadDataByIdentifier service. Reads a data record from the ECU. Format

Input

diag ref in specifies the diagnostic session handle, obtained from Open Diagnostic on CAN FD.vi or Open Diagnostic on IP.vi and wired through subsequent diagnostic VIs. Normally, it is not necessary to manually manipulate the elements of this cluster.
data identifier defines the data identifier of the data to be read. The SAE J1979DA standard defines the values.
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.

Output

diag ref out is a copy of diag ref in. You can wire it to subsequent diagnostic VIs.
data out returns the ECU data record. If you know the record data description, you can use Convert from Phys.vi to interpret this record. You can obtain the description from the SAE J1979DA standard.
success? indicates successful receipt of a positive response message for this diagnostic service.
error out describes error conditions. If the error in cluster indicated an error, the error out cluster contains the same information. Otherwise, error out describes the error status of this VI.
status is TRUE if an error occurred.
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.

Description

The WWH-OBD ReadDataByIdentifier service is based on the UDS ReadDataByIdentifier service (ISO 14229-1).