Q-bert board advice

88mph

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I have a Q-bert here that boots to colored horizontal lines (and no gameplay, etc) upon powerup. I have tested the CPU board in another, known working cabinet and still get the horizintal lines on that machine. I have also swapped in a known working CPU chip with the same results. All of the eproms have been pulled and tested good against known good ROM images. Cleaning and reseating the eproms did not have an effect.

Is this a common problem (horizontal lines) on these board?

Tonight I'm going to hook up my logic probe and see if I can find any activity on the clock pin of the CPU. Are sockets a big concern with these boards?
 
There is a test mode for the machine (the test switch is in the coin door); putting the machine in test mode doesn't change anything, on my cab or the known working cab. I am not aware of a test mode accessible from a dip switch setting on the CPU board itself.
 
No, sockets on these are normally not a problem since they are dual wipe. Of course it can be a problem if there is acid damage. Post a pic of the area around the battery.
 
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