OP

Quoted from Cheddar:

On a Pink Panther (6 digit) I have a single display that the h segment (the 1) lights up whenever the g (middle horizontal line) is lit. I followed the UDN6118 test instructions listed here: https://www.pinwiki.com/wiki/index.php?title=Gottlieb_System_80#UDN6118_and_Other_Display_Logic_Chip_Failures on Z1 and everything was as expected. I also tested for shorts between pins 3 & 4 on the glass and 7 & 8 on the connector.
The problem moves with the display.
Anyone have any other ideas? The display doesn't show any evidence of shorted or broken filaments.

OP

Quoted from Cheddar:

Chris Hibler helped me out on facebook but here is the answer:
I pulled Z1 as there really is only 2 places this issue can be since it moves with the display. I socketed Z1 and put it back in but with pin 11 pulled. This is the driver for the h segment. The logic being if the chip is shorted then the segment cannot be lit, if the segment is lit then the glass is shorted.
Put it in my Joker Poker to test and sure enough the segment was lit. Bad glass is the culprit.
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