Sorry to start another thread on this but the more I read the more I got confused on what the problem is. So here is what I got.

Firepower - The game works but with no sound. Sound did work fine and then just stopped upon power up the next day. The game was sitting for about 5-10 years untouched, I have had it for a week

If I crank up the sound all the way and put my ear to the speaker I can make out all the sounds and speech but barely.

Fuses and fuse holders are good.
Voltages are correct on the sound board. (11.3, -12.5, 4.99)
I removed the driver board, cpu board and sound board and removed and reflowed any suspected pins and then checked all pins with a DMM - All good to the best of my knowledge.
Checked the speaker and volume pot with a DMM and checked good.
Jumped pins 1 and 2 at 10J2 and just get some minor noise (static/crackling) at the speaker but no sound.
No difference if the speech board is pugged in on not.

Any help or direction would be great.

Thanks
Rob

The Diag button did nothing as you expected. The sound board looks untouched so I will order a cap kit and the Amp at IC1 (tda2002). I will report back when I get them installed.

Thanks
Rob

No buzz

I forgot about doing that, its been at least 20 years since I had these older games. I also forgot how great they are.

OK, now I have sound and speech (speech at starting a game, didnt go any further). BUT, the sounds are like a EM, just bings and bongs with no background sound. I reset the settings since I know I was in there messing with stuff. free play, 3 balls and setting 35 is set at factor "12". Testing the sound board with its test switch the sound seem like normal classic firepower sounds. In game nothing but bings and bongs.

I do remember that there were a few games of this era that you could change this kind of thing but its been awhile and I didnt see a setting for this.

Im stumped

Found it, it was the rocker switch on the sound board, I must have hit it and changed it when I had it out. All good now.

Thanks for all the help guys!!

Well I replaced the amp and the caps and still had nothing. So I did some digging and didnt get anywhere, so I called on old friend that is pretty good with this stuff and suggested replacing the two chips on the speech board. They were the two 8 pin chips by the volume pot on the speech board. He sent them to me so I dont remember that the part number that was on them. That fixed it.