Do we need to connect 12V supply to P3-03 to check the LIN output on logic Analyzer.
Hi,
not sure what kind of board do you use, but guess e.g. DEVKIT-MPC5748g.
The LIN transceiver have to be powered so you should connect 12V to P3.3, as you wrote. If you power DEVKIT by 12V power supply you can connect J13.1 to P3.3.
BR, Petr