Sudden Increase Vampire Drain

[MarcG]

Well well well, this morning I'm greeted with a "12V battery needs service" message. So my drain may simply be trying to keep the 12V battery alive.
It's strange that these batteries last so little (I took ownership in Dec 2014).

Time to call service. I hope it's covered by the warranty.

How's your P85D treating you? I also got delivery in Dec 2014 but no 12V battery issues so far, knock on wood!

 

[MorrisonHiker]

I wonder if Tesla enabled the map generation with a new firmware update... however, it would only really explain increased drain with AP2 hardware though, so it's probably not the case here... something to think about though.

Essentially, mapping is one of the unmentioned pillars of FSD that Tesla never talk about. I would imagine they're going with Nvidia's solution, which is part of the capabilities of Driveworks/DrivePX2...

Instead of sending out loads of specially equipped 3D lidar style mapping vehicles, they crowd source HD maps from 'harvesters' - any vehicle with a camera. They start with pretty decent resolution 2D maps (most likely from HERE maps), then refine or build HD maps, using motion and localisation data collected from the cameras.

End-to-end HD Mapping for Self-Driving Cars | NVIDIA

Obviously, you can't send back raw video to the data centres, so it actually crunches and pre-processes a LOT of information on the harvester itself - in Tesla's case, the DrivePX - before uploading the relevant information in a very compressed form to the data center. It really only does this intensive pre-processing when it's not actively driving - for obvious reasons. So, in Tesla's case, I would imagine that whilst the car isn't moving, it's crunching data it's collected from your recent trips. It may also explain how the car can seemingly get a bit 'better' on AP even without FW revisions - the HD map tiles it pulls down every 10km have been generated, or are more accurate.

tl;dr - your car is creating HD maps whilst you're not driving it.

Starting January 1st, I started noticing the fan noise coming from above the glove compartment (where the PX2 is located). Many times in January, I would hear the noise whenever I opened the car door, so it was obvious that it was doing something. I haven't noticed the sound recently so either it doesn't run as often as it did the first month or maybe I've just become used to it. I'll have to listen for it and see if I can still hear it.