Parked Car Losing 20 Miles / Day of Range

[M3Nicola]

My car was recently parked at the airport. High temps in the mid-50s F, lows in the low 40s. Sentry mode is on. I was surprised that may car lost about 20 miles of range every 24 hours just sitting there. Is that normal? I’m on version 2019.8.5. Anything I can do besides turning off Sentry mode to reduce this?

 

[kengchang]

Normal with Sentry Mode on

 

[whatthe2]

Yes normal. Sentry Mode uses about 1MPH, give or take depending on how much it triggers.

I left my car at the airport for 127 hours and it used 135MPH of range. I also had a 2CH BlackVue running.

 

[BOBEDIGITL]

Definitely what the others said above. Losing 20 miles in 24hrs seems pretty good, even if it's not being triggered all that much. I lose about a mile every hour when I leave it parked in my driveway.

 

[Twiglett]

didn't read the note about sentry mode and battery drain in the manual then?

 

[M3Nicola]

Thanks for the replies. Out of the 20 miles / day, approximately how much of that is associated with Sentry Mode?

 

[BOBEDIGITL]

Thanks for the replies. Out of the 20 miles / day, approximately how much of that is associated with Sentry Mode?

I'd say its responsible for at least 50%-75% of the battery drain you described...

 

[srs5694]

I've had my Model 3 for barely over a week, so what I'm about to say is based more on what I've read than on personal experience, but.... Normal "phantom drain" on a Model 3 seems to be in the 2-5 miles per day range, assuming moderate temperatures. It will go up in extreme temperatures, when using Sentry Mode, or when frequently pinging the car by opening the Tesla app. (When you don't pester the car, it eventually goes into a "sleep" mode in which it shuts down many of its systems to save power. Opening the app prevents this from happening, or causes the car to "wake up" to respond to your app. As I understand it, Sentry Mode does the same thing; it's a lot like checking the app frequently enough that the car never goes to sleep.)

 

[SSedan]

I would think constantly checking the app contributes as well.

 

[whatthe2]

I've had my Model 3 for barely over a week, so what I'm about to say is based more on what I've read than on personal experience, but.... Normal "phantom drain" on a Model 3 seems to be in the 2-5 miles per day range, assuming moderate temperatures. It will go up in extreme temperatures, when using Sentry Mode, or when frequently pinging the car by opening the Tesla app. (When you don't pester the car, it eventually goes into a "sleep" mode in which it shuts down many of its systems to save power. Opening the app prevents this from happening, or causes the car to "wake up" to respond to your app. As I understand it, Sentry Mode does the same thing; it's a lot like checking the app frequently enough that the car never goes to sleep.)

Sentry Mode basically keeps the car awake at all times, then it records events once its triggered. So, stands to reason that it will use more range. 1MPH is not bad at all, IMO, for the security of recording events.

 

[M3Nicola]

Sentry Mode basically keeps the car awake at all times, then it records events once its triggered. So, stands to reason that it will use more range. 1MPH is not bad at all, IMO, for the security of recording events.

No, not that bad, accept when you’re parking your car for a long period of time (like at an airport). I’m nervous that many people will come back from a vacation with a dead battery because they had no idea the drain Sentry Mode causes.

 

[whatthe2]

No, not that bad, accept when you’re parking your car for a long period of time (like at an airport). I’m nervous that many people will come back from a vacation with a dead battery because they had no idea the drain Sentry Mode causes.

I left mine st the airport for nearly a week. I was expecting higher drain due to more activity, but still averaged. 1MPH loss.

Sentry Mode will shut off at 20% battery, so if someone comes back to a dead battery they would have to be there for several weeks. It’s not like the battery is going to go dead in a week or two.

 

[jkoya]

Out of curiosity - how many files did you have on your flash drive/memory card when you got back from the airport ?

 

[whatthe2]

Out of curiosity - how many files did you have on your flash drive/memory card when you got back from the airport ?

I don't remember the exact number of files, I think it was around 1,800. I do remember it was 68GB worth of data.

 

[jkoya]

I don't remember the exact number of files, I think it was around 1,800. I do remember it was 68GB worth of data.

Wow - close to the size of some 4K Ultra HD Blu-Ray disc sizes.

 

[whatthe2]

Wow - close to the size of some 4K Ultra HD Blu-Ray disc sizes.

Yeah, good thing I didn't have any damage, would have taken me a while to find the right clip. But, Sentry Mode is well worth it, as I think we've all seen from some of the recent posts catching people hitting/keying their car.

 

[Wennfred]

Before exiting the car, I ensure that the air or A/C is completely off, I was noticing some drain even with Sentry mode off, so turning off the A/C before leaving the car did the trick, no drain in 8 hours since I last checked.

Fred

 

[srs5694]

Sentry Mode is well worth it, as I think we've all seen from some of the recent posts catching people hitting/keying their car.

I'm not convinced of that. Let's do some math. According to the EPA, a Model 3 LR gets 259 Wh/mi, so at 1mph of range loss, that's a consumption of 259 watts. Let's say that you leave Sentry Mode active for 8 hours per day, 365 days a year. That works out to about 756 kWh per year. IIRC, the national average cost of electricity is $0.13/kWh, so that's about $98/year. (I'll round up to $100/year, since that's a nice even number.) That value will obviously go up if you leave Sentry Mode active more, or down if you use it less. (I picked 8 hours a day based on the assumption that you're leaving it active when it's parked in a parking lot at work on a daily basis, and for similar periods when running errands and whatnot on weekends.)

Personally, in 30 years of car ownership, I've had no break-ins and only two incidents that even might have been vandalism or parking-lot accidents. One time my rear window was shattered when I lived in Boulder, Colorado, about 20 years ago. That might have been vandalism (nothing was stolen), or it might have been blown out in a wind storm, which are common in Boulder. Another time, much more recently, I noticed a deep ding that pierced the paint on my car. That might have been deliberate vandalism or a parking-lot accident. I don't recall what it cost to replace the rear window, but the ding cost about $400 to have fixed, which was under my deductible. Let's assume a similar price for the window repair, which means my repairs for these two incidents totaled about $800. If I'd had a feature like Tesla's Sentry Mode for that entire 30-year period, with similar costs, it would have cost me $3,000. The best-case scenario is that Sentry Mode would have saved me $800, but cost $3,000 to operate. The repairs would have been no less hassle, and suing or filing insurance claims against the perpetrators would have been more of a hassle. Overall, this doesn't look like a winning proposition from a selfish economic perspective and based on my personal experience with parking lot accidents or vandalism.

That said, there are caveats and exceptions, such as:

• My experience may not be representative. I don't happen to have statistics handy on how common break-ins, parking-lot accidents, and vandalism are.
  
• Teslas are more expensive cars, and are more expensive to repair, than the cars I've owned in the past. (The blown-out window was on a 1992 Saturn SL, and the door-ding was on a 2016 Chevy Volt.) This will shift the balance in favor of Sentry Mode.
• More judicious use of Sentry Mode may well be worthwhile -- if you're parking the car in a particularly risky area for an hour a week, it may be worth using, for instance; the probabilities shift in this sort of scenario.
• The cost of electricity varies greatly from one area to another. If your electricity is cheap, it'll make Sentry Mode more worthwhile. Of course, it becomes less worthwhile if electricity is expensive where you live.
  
• If/when thieves, vandals, and careless drivers learn that Teslas (and, eventually, other cars) may be recording their mistakes and misdeeds, that may serve as a deterrent. OTOH, this effect has Orwellian overtones that may contribute to an eventual backlash, so I'm not convinced it's 100% positive.

When we see videos of Sentry Mode catching an accident or vandalism, and the owner of the Tesla therefore having an easier time getting redress for the damage, we suffer from various cognitive biases, such as the availability heuristic -- we see, and remember, the one incident of Sentry Mode providing a benefit to the owner. We don't see the thousands of recordings that show absolutely nothing, much less the money spent on keeping those cameras running to record absolutely nothing of interest. If we had to wade through all those recordings, too, we'd be less likely to say that Sentry Mode is such a wonderful feature.

Of course, this analysis could also change if Tesla could bring down the energy costs of running Sentry Mode. Based on my limited understanding, I doubt if this will happen for current cars; but if Tesla (or somebody else) wanted to, a security system with less electricity overhead could almost certainly be built.

 

[whatthe2]

I'm not convinced of that. Let's do some math. According to the EPA, a Model 3 LR gets 259 Wh/mi, so at 1mph of range loss, that's a consumption of 259 watts. Let's say that you leave Sentry Mode active for 8 hours per day, 365 days a year. That works out to about 756 kWh per year. IIRC, the national average cost of electricity is $0.13/kWh, so that's about $98/year. (I'll round up to $100/year, since that's a nice even number.) That value will obviously go up if you leave Sentry Mode active more, or down if you use it less. (I picked 8 hours a day based on the assumption that you're leaving it active when it's parked in a parking lot at work on a daily basis, and for similar periods when running errands and whatnot on weekends.)

Personally, in 30 years of car ownership, I've had no break-ins and only two incidents that even might have been vandalism or parking-lot accidents. One time my rear window was shattered when I lived in Boulder, Colorado, about 20 years ago. That might have been vandalism (nothing was stolen), or it might have been blown out in a wind storm, which are common in Boulder. Another time, much more recently, I noticed a deep ding that pierced the paint on my car. That might have been deliberate vandalism or a parking-lot accident. I don't recall what it cost to replace the rear window, but the ding cost about $400 to have fixed, which was under my deductible. Let's assume a similar price for the window repair, which means my repairs for these two incidents totaled about $800. If I'd had a feature like Tesla's Sentry Mode for that entire 30-year period, with similar costs, it would have cost me $3,000. The best-case scenario is that Sentry Mode would have saved me $800, but cost $3,000 to operate. The repairs would have been no less hassle, and suing or filing insurance claims against the perpetrators would have been more of a hassle. Overall, this doesn't look like a winning proposition from a selfish economic perspective and based on my personal experience with parking lot accidents or vandalism.

That said, there are caveats and exceptions, such as:

• My experience may not be representative. I don't happen to have statistics handy on how common break-ins, parking-lot accidents, and vandalism are.
  
• Teslas are more expensive cars, and are more expensive to repair, than the cars I've owned in the past. (The blown-out window was on a 1992 Saturn SL, and the door-ding was on a 2016 Chevy Volt.) This will shift the balance in favor of Sentry Mode.
• More judicious use of Sentry Mode may well be worthwhile -- if you're parking the car in a particularly risky area for an hour a week, it may be worth using, for instance; the probabilities shift in this sort of scenario.
• The cost of electricity varies greatly from one area to another. If your electricity is cheap, it'll make Sentry Mode more worthwhile. Of course, it becomes less worthwhile if electricity is expensive where you live.
  
• If/when thieves, vandals, and careless drivers learn that Teslas (and, eventually, other cars) may be recording their mistakes and misdeeds, that may serve as a deterrent. OTOH, this effect has Orwellian overtones that may contribute to an eventual backlash, so I'm not convinced it's 100% positive.

When we see videos of Sentry Mode catching an accident or vandalism, and the owner of the Tesla therefore having an easier time getting redress for the damage, we suffer from various cognitive biases, such as the availability heuristic -- we see, and remember, the one incident of Sentry Mode providing a benefit to the owner. We don't see the thousands of recordings that show absolutely nothing, much less the money spent on keeping those cameras running to record absolutely nothing of interest. If we had to wade through all those recordings, too, we'd be less likely to say that Sentry Mode is such a wonderful feature.

Of course, this analysis could also change if Tesla could bring down the energy costs of running Sentry Mode. Based on my limited understanding, I doubt if this will happen for current cars; but if Tesla (or somebody else) wanted to, a security system with less electricity overhead could almost certainly be built.

I’ll change my comment:
Sentry Mode is well worth it, as I think some of us have seen from some of the recent posts catching people hitting/keying their car.

 

[srs5694]

When we see videos of Sentry Mode catching an accident or vandalism, and the owner of the Tesla therefore having an easier time getting redress for the damage, we suffer from various cognitive biases, such as the availability heuristic -- we see, and remember, the one incident of Sentry Mode providing a benefit to the owner. We don't see the thousands of recordings that show absolutely nothing, much less the money spent on keeping those cameras running to record absolutely nothing of interest. If we had to wade through all those recordings, too, we'd be less likely to say that Sentry Mode is such a wonderful feature.

I’ll change my comment:
Sentry Mode is well worth it, as I think some of us have seen from some of the recent posts catching people hitting/keying their car.

Please re-read what I wrote about availability heuristic bias.