The P1961 collection groups A2L ECU Calibration Definition File resources that share a brand, ECU identifier, or software family on one stable page. Hardware numbers, software releases, and technical branches remain visible so nearby versions can be compared through search results and internal links.
When selecting a P1961 resource, compare the vehicle or engine, ECU hardware number, software number, real file type, and original technical filename. An A2L or DAMOS definition must match the actual ECU read; the brand name alone is not sufficient evidence of compatibility.