System legacy CMOS battery is depleted.
System legacy CMOS battery is depleted.
I have a motherboard issue because the CMOS is dead, and it seems the BIOS settings aren't being saved. The battery isn't a CR2032 but an old lithium block that's soldered directly to the board. No one has any suggestions to fix this without soldering the components. You're planning to leave it on during lunch to check if it charges or retains power. You can see the CMOS battery in the second photo.
It might be possible to drill into the outer plastic or cut the case with a sharp tool, checking for any epoxy residue. If found, you could inject power from another source or swap out the old lithium cell. A battery holder using two AA batteries and a diode in series could work as an alternative, though you'd need to solder the connections.
I checked the part number (M48T86PC1)—it includes an integrated battery with the RTC. This means the black module isn't just a battery; it also functions as a clock, so swapping it for a new one isn’t possible. The only solution is to remove the entire module, which involves desoldering the old part and soldering a replacement. It looks like a through-hole design, making it somewhat manageable, though I’m unsure of your soldering expertise. Looking at the datasheet, Vcc is pin 24 and GND is pin 12 (unless you have the 28-pin version, then it’s 27 and 13/14—but that seems unlikely). You might consider using an external 3V supply connected to those pins, as suggested by @mariushm. This approach feels a bit hacks, so if you can, replacing the whole chip would be simpler.