Quite often anything that comes on - heats up and goes off is either a bad wire connection or dry solder joints. Check the basics first. Make sure the cables on the header connectors are making good contact or re-pin them and check all header pin solder joints (just reflow them anyway)

When I look at that two things jingle in my head:

1) power issue to the display (connector - dry joints etc)
2) decoder IC chip maybe faulty

Definitely check the first one first. Use display 1 for reference measurements...