Baby pac-man help

[bigh4th]

I got my girlfriend a baby pac-man off of ebay almost a year ago as a birthday/anniversary present.  After a few nights of cleaning boards and contacts (yes, the 26 y.o. battery was still on the board)  I got it working.  It worked for a few nights, but par for the course, it wouldn't boot as soon as the girlfriend came over and turned it on.

So now that I've finaly gotten the time to mess with it again,  Ive done some work on it and done some component replacement.  I've gotten to the point where I'm getting the correct number of flashes from LEDs on the vidiot and MPU boards, but it still won't boot the title screen.  Here's where things get strange...

If I push the coin-door test button, the game will go into test mode with a dead screen.  However, If I push the test button on the vidiot board, it will bring up the proper image on the screen all the way through the tests using the coin door button, with proper transmit and receiving information on the communication screen.  As soon as you finish the test and the game resets, it goes back to the dead screen.

I have swapped just about every removable chip on the board with 2 others with no change. 

Does anyone have any idea what would be causing this problem? 

-Harry

[2PacMan]

I've always read that replacing the connectors on this game can fix many of its problems.

[solderguy1]

Maybe the tms9928 is acting up?  You can get another to try from a colecovision if need be.

You probably know about Clay's guides, but just in case:

http://www.pinrepair.com/bally/babypac.htm
http://www.pinrepair.com/bally/index1.htm