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Vampire drain while still plugged in after charging session completed?

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PoitNarf

My dog's breath smells like dog food
Jun 7, 2016
2,889
4,337
NJ
So after a day of around 2.5-3 hours total of driving I noticed that my range went down pretty significantly for the distance I actually travelled. Plugged in last night and the charging session completed shortly after midnight and reported a range of 273 miles on the Tesla app. I just checked it again approximately 18 hours later and my range has dropped to 265 miles. The car has been plugged in and parked in my garage all day. I haven’t even unlocked the doors. A loss of 8 miles in just 18 hours while it’s still plugged in?

This doesn’t strike me as normal. Anyone else seen behavior like this? Will the Model 3 still lose range due to vampire drain when it’s plugged in (although not currently in a charging session)?

I’m wondering if this is related in some way to the “Charge Port Door Needs Service” message I started receiving yesterday morning after washing my car. In any case I’ll be calling Tesla service about the charge port door and will also mention the increased vampire drain I’ve noticed.
 
So after a day of around 2.5-3 hours total of driving I noticed that my range went down pretty significantly for the distance I actually travelled. Plugged in last night and the charging session completed shortly after midnight and reported a range of 273 miles on the Tesla app. I just checked it again approximately 18 hours later and my range has dropped to 265 miles. The car has been plugged in and parked in my garage all day. I haven’t even unlocked the doors. A loss of 8 miles in just 18 hours while it’s still plugged in?

This doesn’t strike me as normal. Anyone else seen behavior like this? Will the Model 3 still lose range due to vampire drain when it’s plugged in (although not currently in a charging session)?

I’m wondering if this is related in some way to the “Charge Port Door Needs Service” message I started receiving yesterday morning after washing my car. In any case I’ll be calling Tesla service about the charge port door and will also mention the increased vampire drain I’ve noticed.
Yes... The Model 3 doesn't have the SLEEP mode and other improvements that the S had added subsequently...

The vampire drain on the model 3 still needs a lot of fixes... That's why I do the math and back up from it on when I plan to leave...
 
Yes... The Model 3 doesn't have the SLEEP mode and other improvements that the S had added subsequently...

The vampire drain on the model 3 still needs a lot of fixes... That's why I do the math and back up from it on when I plan to leave...

I just found it odd because while I have observed previous vampire drain this seems to be at least 2x what I would normally experience in a typical day in my 2 1/2 weeks of ownership thus far.
 
I’m wondering if this is related in some way to the “Charge Port Door Needs Service” message I started receiving yesterday morning after washing my car. In any case I’ll be calling Tesla service about the charge port door and will also mention the increased vampire drain I’ve noticed.

Which firmware do you have? I had the Charge Port Door Needs Service message and when my firmware updated from 2018.4.? to 2018.12.1, the message stopped popping up for the 2 days before my previously scheduled Tesla Mobile Service replaced it anyway.
 
I'm on 12.1 as well.

Well I'm glad the tech talked me into replacing the part as scheduled since you have 12.1 and its still occurring for you. It's difficult to figure out whether a lot of the bugs reported are firmware related or hardware related. I can live with the occasional reboot with software problems, assuming it'll get fixed with an update. I would rather not deal with the hassle [albeit minor] of setting up appointment and dealing with the downtime for repair, only to find out it was software related. I've had 2 such hardware repair/replacement that might have resolved with just software updates. I decided I'm just going to timestamp when I notice things and call for service only if it affects vehicle function.
 
Same thing happening here. I charged to ~60% (181 miles) overnight and it was still at 181 miles this morning. 8 hours later, sitting in my garage plugged in all day, it's now at 175 miles.

I'm on 12.1 and haven't noticed any charge port error messages, but I've had charge port issues. Door will only open halfway sometimes, and yesterday I noticed the charge port light was red.

I've got a mobile service appointment on Friday for an unrelated issue so I'll ask them about it at that time.
 
As background, being still plugged in is somewhat irrelevant to the vampire drain problem. With an EVSE (the "charger", either an HPWC or the UMC), the car signals that it needs charging, and there's a "thunk" in the EVSE where a large relay connects the car to the power. When charging is done, another thunk occurs where the car is disconnected. At that point, it's no different than if the car was totally unplugged (except that the car can't plug itself back in later on). It's not like keeping it plugged in will continuously keep the battery topped off.

That's not to say there's not a problem with vampire drain, just that in a short session (e.g. overnight) it won't matter if the car is still plugged in after the charging is complete or not.
 
As background, being still plugged in is somewhat irrelevant to the vampire drain problem. With an EVSE (the "charger", either an HPWC or the UMC), the car signals that it needs charging, and there's a "thunk" in the EVSE where a large relay connects the car to the power. When charging is done, another thunk occurs where the car is disconnected. At that point, it's no different than if the car was totally unplugged (except that the car can't plug itself back in later on). It's not like keeping it plugged in will continuously keep the battery topped off.

That's not to say there's not a problem with vampire drain, just that in a short session (e.g. overnight) it won't matter if the car is still plugged in after the charging is complete or not.
I see your point, but shouldn't the car maintain a certain level of charge while plugged in? This is my first Tesla, so I can't speak to charging behavior in a Model S or X.

Commenters above and I are seeing several miles fall off after charging complete, while plugged in.
 
I see your point, but shouldn't the car maintain a certain level of charge while plugged in? This is my first Tesla, so I can't speak to charging behavior in a Model S or X.

Commenters above and I are seeing several miles fall off after charging complete, while plugged in.
There's a margin from full charge that the car has to lose before it kicks into the charge cycle again. I don't know what it is for the Model 3, but it's several miles for my Roadster (several percent of full), which typically tops up every few days. Definitely a day(s) sort of thing, not one of hours or minutes. I expect they do this to save wear and tear on the big relays in the car (the "contactor" as they call them) and in the EVSE. But, if the car were to lose charge faster than that (say, you left the climate control on), it should cycle more often to stay within that margin.
 
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There's a margin from full charge that the car has to lose before it kicks into the charge cycle again. I don't know what it is for the Model 3, but it's several miles for my Roadster (several percent of full), which typically tops up every few days. Definitely a day(s) sort of thing, not one of hours or minutes. I expect they do this to save wear and tear on the big relays in the car (the "contactor" as they call them) and in the EVSE. But, if the car were to lose charge faster than that (say, you left the climate control on), it should cycle more often to stay within that margin.
Good to know, thanks for the insight! I'll keep an eye on it over the next few days to see if I notice that behavior.
 
So after a day of around 2.5-3 hours total of driving I noticed that my range went down pretty significantly for the distance I actually travelled. Plugged in last night and the charging session completed shortly after midnight and reported a range of 273 miles on the Tesla app. I just checked it again approximately 18 hours later and my range has dropped to 265 miles. The car has been plugged in and parked in my garage all day. I haven’t even unlocked the doors. A loss of 8 miles in just 18 hours while it’s still plugged in?

This doesn’t strike me as normal. Anyone else seen behavior like this? Will the Model 3 still lose range due to vampire drain when it’s plugged in (although not currently in a charging session)?

I’m wondering if this is related in some way to the “Charge Port Door Needs Service” message I started receiving yesterday morning after washing my car. In any case I’ll be calling Tesla service about the charge port door and will also mention the increased vampire drain I’ve noticed.

Did you ever get this resolved? This just started happening to me this month. The only two changes were the firmware and my charge port door was replaced. I’m leaning on the charge port door since it seems to be a bit too coincidental. I have a service appointment so hoping they can figure this out.
 
Did you ever get this resolved? This just started happening to me this month. The only two changes were the firmware and my charge port door was replaced. I’m leaning on the charge port door since it seems to be a bit too coincidental. I have a service appointment so hoping they can figure this out.

I haven't noticed any serious drain issues for months now. Any issues I was having before were either 1) related to colder weather all the way back in early April or 2) caused by bugs in earlier software versions.

My charge port door was replaced quite a while ago and has been solid ever since.