Script Type Function Block Command: Test DTC

Command Description

The Test DTC command checks the data in a receive message for specified Diagnostic Trouble Codes (DTCs). If DTCs are detected, their data is copied to an application signal.

This command currently supports only J1939 DTCs.

Value Field Parameters

A dialog box opens when you double-click in the Value field, allowing you to specify the DTCs you want to search for, which message to search, and where to store the results. An example can be seen in Figure 1; a full description of the parameters can be found below.

Figure 1: Dialog box to set up a Test DTC command.

J1939 DTC Parameters

Enter the following values for a DTC you want to search for:

SPN: The Suspect Parameter Number (0 to 524,287).
FMI: The Failure Mode Indicator (0 to 31). You can check Don't Care next to this value if you want to ignore the FMI.
OC: The Occurrence Count (0 to 127). Again there is a Don't Care option if this parameter is not relevant.

After making your selection, press the Add button next to the SPN box to add the specified DTC to the large box labeled DTCs to look for in Rx Message.

If you want to enter more DTCs, repeat the process. You can also use the Remove button to delete an entry from the list, or press Clear All to delete all entries.

Send Results to Application Signal

Select the application signal to receive DTC data using the drop-down box here.

Rx Message

Select the receive message to search for the specified DTCs.