Hi @censord
Inspect the display flex cable connector on the systemboard to make sure that no damage has occurred to the pins in the connector.
If the connector appears to be OK, here's the troubleshooting section of the SM-T500, -T505, -T507 service manual that may help.
Go to p.22 (of 29) to view the display/touch screen troubleshooting flowchart. At the end of the flowchart there are layout diagrams showing the location of the components referenced in the flowchart.
Unfortunately there's no parts list in the manual, so if a component is faulty it may be hard to know what type (or value) the component is (or has) so that it can be replaced. Hopefully it doesn't come down to that.
crwdns2934105:0crwdne2934105:0
crwdns2934113:0crwdne2934113:0
crwdns2915270:0crwdne2915270:0
crwdns2889612:0crwdne2889612:0
2