Resolved - Pole Position 2 - Resetting before title screen

[jimk]

Resolved - Pole Position 2 - Resetting before title screen

I'm working on a PP2 board that resets before the title screen. On power up I get the scrambled graphics, a quick flash of the test screen showing no errors, the grid and a start of the title screen. At this point both Z8002 are reset by 8E. I'm suspecting 7J or 7K even though the quick flash of the test screen shows no ram errors.

The issue is not related to power or the cabinet, it is a board problem.

Any help would be appreciated

 

[jimk]

Resolved, it turns out the reproduction 51xx I was using was bad and the custom at 9FA was bad. The bad 51xx was brand new

 

[66GTO]

Confirmed this repair for the same problem I was having with a Pole Position 1 CPU board. I replaced the socket and 54xx chip at 9FA, and the resetting is gone! Yeah baby!

 

[LyonsArcade]

This is the sound custom that creates the explosion sound, which happens just when the title screen comes on... so the reason the game was rebooting was the custom trying to make the explosion sound was causing it. Removing that chip would likely allow the board to boot (it'll play without it) ... it could be the original poster was having an issue because he mentioned it as a 51XX, that's the wrong custom if that's what he really was installing in that spot.