VLC 8825 works... barely.. Guidance Needed!

[marshall212000]

Hi!
I have a VLC 8825 that basically works! (amazing right? here in late 2024) and its giving me a low battery error and incorrect time and date upon boot. T/D error can be corrected thru adjustment in diagnostic menu. however, id like this to function normally which prompts this thread post. I know if the watchdog trips, these things basically become boat anchors. What is the best way to replace the 3 button cell batteries and the 1, 3.7V lithium soldered to the board without causing more ruckus than i currently have? my background is in pinball, and on older games that predate NV RAM its common practice to replace batteries with the game ON to not loose any CMOS data. Does the same logic apply here? is it safe with the game ON and booted, to replace the 3 button cell batteries (1 at a time) and the Lithium cell in an attempt to not lock it up? or should i use a bench supply to inject voltage during this process? any insight would be appreciated.