I PM'ed nat about this, but just posting it here as well for backup. My Turbo Express decided to finally break for good...
It had been sitting in the shelf for many years and recently I wanted to fire up Super Star Soldier on it as I used to do, but now all that happens is that the backlight comes on when I turn it on, but nothing else happens. The game doesn't boot, no sound, nothing, just a black screen with the backlight powered on. I noticed though that there is still input control and screensaver support; I turned it on and left it alone for a couple of minutes and eventually the backlight would turn off, but when I touch any button or the D-Pad, the backlight turns back on and stays on for a certain about of time.
I read in the repair threads that this might be due to the one video capacitor, so I might actually try replacing that myself, but I wasn't sure it quite applied to the situation because the game doesn't boot at all, there is no sound, etc. Anyway, just wanted to put this out there for someone that fixes Turbo Express units. I may just wanna sell it broken or something and be done with it. To ship it to someone, pay for the labor and the shipping of it back to you, it's probably not worth it and I didn't use it all that much anyway...