The "Heimdall failed to download PIT file" error is a common roadblock when flashing custom firmware or recoveries on Samsung devices using the open-source Heimdall suite. This error usually occurs during the initial handshake between your computer and the phone, preventing the software from reading the —the roadmap that tells Heimdall where to write data. Core Causes of the PIT Download Failure
Note4: Heimdall fails to download pit file · Issue #276 - GitHub heimdall failed to download pit file