Need an electronics wiz's advice

[smellsfishy]

you can always check for cold solder joints on the board or even a hairline crack on the board, it may have been dropped and components heatup expand, which may be likely here. the larger components like coils, relays etc. can easily pull the pin through a thin layer of soldier with enough force or if they weren't glued to the board.
9 times out of 10 an electronic fault is caused or a result off a mechanicl or physical problem.
good luck use a magnifiieng glass if you got one.
or try another bulb.