The current version of the Service Manual for my 2022 Tesla Model S has the following in General Information -> Charging -> General:
Discharging the HV battery to 0% state of charge can permanently damage the battery. To protect against a complete discharge, the vehicle enters a low power consumption mode when the state of charge drops below 6%. In this mode, the battery stops supporting the onboard electronics to slow the discharge rate. NOTE When the low power consumption mode is active, the auxiliary 15V battery is no longer being charged and can completely discharge within hours. If this situation cannot be avoided, disconnect LV power (refer to procedure) from the vehicle to preserve the 15V battery. If a complete discharge does occur then the vehicle will need to be jump-started and the 15V battery must be replaced. ======= The Owner's Manual has the following in the Sentry Mode section: Sentry Mode requires your Battery to be at least 20% charged. If the Battery falls below 20%, Sentry Mode turns off and the mobile app sends you a notification. Power consumption may increase when Sentry Mode is active. It has the following in the Battery Care section: Even when Model S is not being driven, its Battery discharges very slowly to power the onboard electronics. The Battery can discharge at a rate of approximately 1% per day, though the discharge rate may vary depending on environmental factors (such as cold weather), vehicle configuration, and your selected settings on the touchscreen. Situations can arise in which you must leave Model S unplugged for an extended period of time (for example, at an airport when traveling). In these situations, keep the 1% in mind to ensure that you leave the Battery with a sufficient charge level. For example, over a two week period (14 days), the Battery may discharge by approximately 14%. Kevin > On Aug 15, 2025, at 8:21 AM, Collin Kidder via EV <[email protected]> wrote: > > Well, they do some of that. Sentry mode will disable at some point, I think > 30% SOC. The car won't enable those sort of "bonus" features at low SOC but > it seems that otherwise it's perfectly fine with trying to kill the HV > battery to save your $200 12V battery and still be able to run the > computers. That does seem to be a rather poor choice. Personally, I'd > rather ruin the 12v battery and leave the main HV battery at 20% or > something. I believe most other current EVs (Bolt, Mach-E, etc) do disable > pretty much everything to do with the HV battery at a certain SOC so that > it stays good even if that means your 12V battery has to die. > > On Thu, Aug 14, 2025 at 9:37 PM Bryce Nesbitt via EV <[email protected]> > wrote: > >> And YES this is a serious design flaw. >> >> The car could implement several battery actions: turn off sentry, camping, >> and eventually LTE data. Have a "battery saver" mode that wakes up >> once a week to call >> Tesla over mobile data, but that's it. >> _______________________________________________ >> Address messages to [email protected] >> No other addresses in TO and CC fields >> HELP: http://www.evdl.org/help/ >> >> > -------------- next part -------------- > An HTML attachment was scrubbed... > URL: > <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20250815/43a9d4ec/attachment.htm> > _______________________________________________ > Address messages to [email protected] > No other addresses in TO and CC fields > HELP: http://www.evdl.org/help/ > _______________________________________________ Address messages to [email protected] No other addresses in TO and CC fields HELP: http://www.evdl.org/help/
