Soft dips not saved

I have an Mv-4f that I recently repaired so that it would pass the backup ram test (replaced both chips). It boots and plays fine now, and saves the calendar info, but soft dips (most notably the cabinet settings) aren't being persisted.

The board has a unibios 3.0 in it and the backup battery was replaced long ago with one of the CR2032 kits from JNX. When I did the repair I replaced the battery, cleaned up some corrosion around the site, and replaced an electrolytic cap that was corroded and had a hole in it.

What's the best way to troubleshoot this? Why / how would the calendar work fine and not the backup ram?

I would start by clearing backup ram then retesting. Its possible it became corrupt when you were repairing it.

If that doesn't help then try checking the voltage for the backup ram when the board isn't connected to your jamma harness. The backup ram are the 2 surface mount chips at G8. Pin 28 on both chips should be around 2.68-2.70V. You should also expect to see that same voltage on pin 14 on HC32 @ G9 and pin 14 on 4990A @ G10

Ya check the battery, if it's like ack said, you need to replace it. I've seen such a wide range of battery life on Neo boards from 1 week to 3 years.

Awesome, thanks guys. Hopefully I'll have some time to work on this tonight.