The whole stern board replacement stinks 1st they are cheap and poorly made fail on a regular basis and then limit the supply and keep prices high the price of the node boards has rocketed up also we are punished with the frequency differences electrocoin offer an advanced replacement but it's still not cheep and that's if they have them in stock
It needs someone to study the boards and work out what is failing on them my guess is it's the same component every time as it's always the same fault but as stern won't release the schematics and a lot of the chips don't have pn on then it's not that easy
There is a microcontroller on the node board, the board is effectively a blank canvass. When the game powers up, the microcontroller has a bootloader, and it sits and waits. The CPU (master node) in the backbox then sends the game specific node board code to each node board over the serial data lines and then the game is ready to go.
When you get the node board not initialised message, it means it was unable to download code onto the node board for whatever reason. For this to be the case, you would assume that either the microcontroler has failed or there is a power issue. It's unlikely that holding a flipper would kill the microcontroller as they are not directly connected, so its more likely that there is an SMT fuse or something on the board, and Stern just charged this guy £258 to change a SMT fuse
Given a Spike machine, a logic analyser and a lot of time and patience, you could probably reverse engineer the bootloader code for the microcontroller, this is the only thing stopping you from reproducing the board, and this is why Stern will make you send the board back, they can't have people playing around with the boards and fixing them or reproducing them, as that would put an end to them charging £258 to change a fuse.
I don't think I say it enough, but seriously, f*** Stern