Hello everybody! I'm trying to repair a Firepower 2, but i have mpu
trouble.
As soon as i turn the game on, the LEDs are on constant and
code 4 is on the segment led, which would mean a bad rom at ic17.
Shouldn't the LEDs be displaying 0 and locked on?
Then pressing the diag. button an error code should come up.
I have already change all the sockets (also for CPU) and ordered new roms set for it.
Why I don't have the "zero"???
Thanks a lot!!!

Ciaooo

Bump

Thanks Chris for your answer.
My doubts are because in every guide on the web, for a locked mpu I must have the "zero" on the mini display.
Every other number (from 0 to 9) will be displayed only pressing the diagnostic pushbutton.
I've tried another set of ROM (from my Time Fantasy). Ok, they are not tested and I don't know if they function. But I have always the same code 4 as soon as the board is powered on. A coincidence?

Is my first sys7... I've a little bit of familiarity with sys4 to 6, but these sys7 seem completely different! .. my first time
So, the sockets are been already changed. Also the 6808 socket. I tested with multimeter the continuity between pads & tracks and they are ok. One of my limits is that I don't have any eeprom programmer, so I always have to buy from thirds (thanks J. Wart for your service!).
I also bought the Leon test rom for sys7... I have to wait its arrival then I will check the board behavior.
I saw the differences between jumpers, and the actual IC17 is a 2532 and the board is setted right..
When I come back to home after work, I will try to pull off the ROMs and to power the board... finger crossed for the zero!
Could a PIA error do this kind of trouble?

News... maybe could help for the diagnosis.
I pulled off all the ROMs and the display, when the mpu is powered on, shows the "standard" error code zero.
Unfortunately, even today I haven't received the new set rom...

With Leon test ROM in IC17, the leds and "zero" on the display blink as per program. With probe I've tested all the outputs of PIA 18 & 36 and I had no signal on pin 9 of IC36. I changed with new one but the same result... no activity.
Now, with the new romset, as soon as I turn the power on, the display show "1" (and only the lower led is on). I am a little bit confused...

It's good to know...
With Leon test rom, the zero and LEDs start to blink, then when I press the diag. button I immediately have the "1" displayed with the lower led lit.
But I also have this error code when I turn on the board...
Which alternatives you mean? Andre boot for example? I also have Leon test rom for sys 3 to 6 and works great...

Your argument is flawless!!! The "1" indicates two different issues.
And my principal problem and though is why I have the "1" on booting.
With old romset the code was "4", and now is changed to "1".
I've already changed all the sockets (double leaf) for the roms and the 6808 cpu. Also I socketed IC36 (I thought an error due to inactivity at pin 9). IC13 and IC16 are directly soldered on the board, as the 5101 chip. With Leon tes rom, the output of IC18 (pin 2 to 17) are ok, so this PIA could be considered fine. Where I can check? Unfortunately I've only this Leon test rom... and my multimeter / probe.
Have you any suggestions about?
The batteries have lost acid in the past, but in a previous repair, someone has cleaned and changed the damaged parts without solving the problem. So I offered my help to this "old guy", 'cause my familiarity with sys4 to 6. Now I don't want to make a bad impression

Here two pics of the board, maybe they could help.
If anyone has some suggestions for me, is welcome!!!

Component_side.jpg

Solder_side.jpg

Hi to everybody! I'm resurrecting this old post only to inform you that the cpu board passes the bench test. The problem was a bad RAM in IC 16 (I changed also IC 13 ...)... Now I'm waiting my friend for a complete test report of the boards installed in its pinball!!!
Thanks guys