So I'm trying to have that Bone Busters I bought last autumn working.
The whole playfield was so sunburnt I had to find a new one, and reinstall all the parts of the first one on it. Almost done.

But the main issue I have is that it doesn't boot.
Or actually, it starts, The lights on the playfield look like a normal attract mode, but there's a permanent beep coming out of the speakers.
Also, what appears on the displays can be totally random. It changes everytime I turn it on.

Here's an illustration :

Well... By tilt switches, slam and normal, you mean those "blade" connectors (absolutely not sure of the term in English, sorry bout that!) and those with a pendulum or a ball on a sort of a gutter?
I checked them... but nothing...

And I've also checked the connectors around the boards in the backbox, using a connection spray, but nothing more... I'll take a bit more time tomorrow.

Thanks anyway, guys.

Well, well, well...
I've spent part of the afteroon yesterday replacing the playfield of this machine... I had to do it, it was totally burnt on some parts...
IMG_20150521_212221150.jpg

And doing this, I discovered that some connections had been... let's say "modified"
IMG_20150521_212410527.jpg

So I checked all of that, noticing that some of the welding done could touch the pin next to it.
I thought this could probably be the origin of my problems..

But once I had finished all of that, the issue was still here.

So I checked the +5 supplying the CPU board, and it was a 4.9, so I adjusted it. No change.

and the ground is all good.

SO, a few things to be noted :
IMG_20150515_140134615.jpg

* the red led on the left hand board (?) is on when i start it, but doesn't flicker.
when i booted with the cpu board unconnectd, it did...

* the Eproms seem not to have stickers on them anymore (well, actually, that's a fact).
Could it be the problem??

Is the driver board the one below the cpu board?? (I'm sorry, the tech doc i have is only 20 pages long, so I lack a lot of the data on it...)

Okay.
So yeah, no change when I disconnect the CPU board from the Driver board.

yfz450 told me by mp to check the temperature of the riot chips... I've started a quest to know what these are. But I've got my little idea...

Well... My U4 is burning hot after a few seconds on...
I guess my problem could reside around here, don't you think?

Extraction tools..?
Hmmm... You mean after unsoldering the pins, I'll struggle to remove it??
IMG_20150525_200430024.jpg

I probably should find a professional to do that, then..(?)

Should I buy and replace just one?