I've got a bizarre one for you.

So the past month I've been away from home due to family emergencies across the US. I've barely had any time to be with the car, so it just sat in the driveway. Well, after having sat for only a few weeks, I went to open it and nothing happened. Figured my keyfob was dead and unlocked it manually, but noticed the interior lights didn't come on either. Didn't have time to deal with it before hopping a plane so I used another car instead.

When I finally got back a few days ago, I checked the battery and it had 1.2V. Not a typo. Had bought the battery brand new back in May, but figured okay, maybe defective. The '90 has been sitting in our garage for even longer and it still reads 10.6V (before I put the tender back on it). So I got the battery replaced under warranty, tossed it on the car, and that brought everything back.

Except that now my odometer reads 0.

How in the actual fuck? Isn't the CCM's userspace NVRAM? It's not supposed to care if there's no voltage, right? Why would a near-dead battery cause the CCM to reset? Has anyone even heard of this? Anybody know why?

I have a dump from the '95 I took before, and I have a photo on my phone showing I hit 129,000 miles on September 17th of this year, so I won't be up shit creek reflashing it. But I'm just...flabbergasted.