After having had two Hobbit book displays die on us in less than a year, I decided to have a closer look and examine the electronics inside the display housing.
When electronic circuits fail, they fail for a reason – and brand new PCBs shouldn’t fail at all. The most likely culprits causing breakdowns in pinball machines are short circuits (resulting in smoke, blown fuses or burnt components) and vibrations (causing all sorts of mechanical and electromechanical issues).
No fuses had blown and everything else seemed to be working ok. I suspected vibration damage.
I unplugged the display, removed the VGA connector housing along with the 4 nuts holding the metal enclosure in place. I then detached the flex PCB that runs between the display module and the driver PCB, enabling me to inspect the PCB under the microscope. What I found was somewhat disappointing.
It turned out that all solder joints on through hole components on both displays were bad. Way too little solder had been applied at the factory, resulting in a highly vibration sensitive module. It was working when it left the factory, but premature failure was almost guaranteed for these displays.
Resoldering these components resulted in working displays. Easily fixable, but annoying.