This article explains where Datacom Datadictionary DDPFLD00* error messages are documented.
DATACOM DATADICTIONARY
15.1
Refer to DATACOM MESSAGES where DDPFLD00cc is documented. See section "Record/Table Field Maintenance Panel Error Codes" where the list of cc error codes is explained:
In this case,
T3 The number of decimal positions specified exceeds the length of the FIELD entity-occurrence.