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Newbie Vampire Drain and Charging Questions

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So I have had my new MS 75D for a week and had to leave her behind for a business trip. I’ve been checking in with the phone app and TeslaFi and I’m losing almost 10 miles of range a day. Ok so that seems a bit high but I did leave power save off and always connected on....hey I wanted to make sure I could talk to her while gone. Even so that seems a bit high for drain.

What really concerns me is I left her plugged in albeit to a 115v outlet. I would have thought leaving her plugged in would have kept the battery from discharging, what am I missing? I have charge set to 80% does it have to discharge a certain amount before it recharges? I just assumed the car would be running off the “shore” power and not draining the battery at all. I can manually start a charge so I know it is getting power. So somebody set me straight.
 
I would have thought leaving her plugged in would have kept the battery from discharging, what am I missing? I have charge set to 80% does it have to discharge a certain amount before it recharges? I just assumed the car would be running off the “shore” power and not draining the battery at all. I can manually start a charge so I know it is getting power. So somebody set me straight.

The car will recharge when you have lost more than 3% capacity of the battery, in your case when the car reaches 76%. If you have scheduled charging, it will wait until the selected time.
A lot of things run on 12v which is what is causing the drain, and this uses power from the 12v battery. However, since the 12v can only be charged with the battery pack, and not with shore power, there will be a drain from the battery pack and not shore power.
 
Per TesLab I have lost 32.9 miles, or 15% in the last 22 hours due to phantom drain. The only Tesla apps I'm using are Dashboard for Tesla and Teslab. I maybe check my car once every 12 hours so it isn't me waking up the car.

Smart preconditioning is off, but overheat protection is on. But we have had pretty mild days so I don't think the interior temp has approached 105 degrees.
 
I maybe check my car once every 12 hours so it isn't me waking up the car.
What about Teslab? Dashboard? They may completely prevent sleep mode. Car does not push any info, it has to be pulled, so the apps have to constantly ping the car to see if anything happened - a new drive, charging started, or finished, etc.
 
So I see my car is charging after it drops 3% so it appears to be working fine I was just a little surprised by the amount of drain. I had my girlfriend turn on power save and it now goes to sleep. However when she did this she noticed I have a 12v battery needs service message. The car is 2 weeks old and has 400 miles on it and it needs a new battery? Is there a way to reset this message and see if it returns? She already rebooted the display but it is still active. Time for my first service call I guess.
 
The age of the 12v battery not necessarily correlates to the age of the car and could be much older (or defective). Batteries die very suddenly and when it does, you will not be able to start the car. I'd call SC and replace it.
 
I found I lost about 2 miles’ range per day. Left my car for 4 days parked in a hotel car park at temperatures between -1 Celsius and 8 Celsius. Preconditioning off. Energy saving on. Always connected on. Checked range status once per day with the Tesla app. Seems OK to me.
 
Update: Tesla sent a Ranger out and replaced my 12v battery. Haven’t been home to check it out but it seems strange to me that a 12v battery would fail that quick. I guess it is possible it was sitting in a warehouse before going to the factory but i’ve never had a battery fail that quickly.
 
From what I learned by testing the current and the voltage of the 12 battery of my X, the app call has very little effect on the added consumption when set Energy saving off, because:
1. the car is awake (the DC-DC is on) most of the time, and there are 4 remote calls from/to the Tesla server anyway.
2. a remote call (app call included) only adds a positive spike to DC-DC current when it is on which consume little extra energy.
3. a remote call (app call included) does consume some energy of the 12V battery when the DC-DC is off but does not wake the car up, and the time period is usually not likely people call the car.
4. the DC-DC is off and the car enters into sleep mode at 23:00 to 5:30 every day local time.
20180320-png.288755
 
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FWIW, here are my “vampire drain” experiments showing different settings and with and without (dual channel) dash cams.

Unplugged. In California based garage with an average overnight temperature of 61°F (~16° C if memory serves). Also typically do not check Tesla app while away (and if I do, no more than once). I do not use third party apps that poll the car. As always, YMMV (literally!), but this is my fairly controlled data in case it is at all helpful.
 
I'm a heavy user of TeslaFi and Dashboard for Tesla.

The following settings are requureq to let the car to sleep (and reduce vanpire drain less than 3 miles in 24 hours):
- turn on power saving mode
- turn off always connected checkbox
- uncheck both temperature monitoring checkboxes in TeslaFi
- enable TeslaFi sleep mode
- don't use any apps or other services during the time the car is trying to sleep

Dashboard for Tesla causes the car NOT to sleep in my experience, if you use any of its background services.
 
From what I learned by testing the current and the voltage of the 12 battery of my X, the app call has very little effect on the added consumption when set Energy saving off, because:
1. the car is awake (the DC-DC is on) most of the time, and there are 4 remote calls from/to the Tesla server anyway.
2. a remote call (app call included) only adds a positive spike to DC-DC current when it is on which consume little extra energy.
3. a remote call (app call included) does consume some energy of the 12V battery when the DC-DC is off but does not wake the car up, and the time period is usually not likely people call the car.
4. the DC-DC is off and the car enters into sleep mode at 23:00 to 5:30 every day local time.
20180320-png.288755

BEST GRAPH EVER!!