4% battery drain in 10 hours whilst parked

[AMP_it_up]

I've had by M3P over just over a year and done 14k miles. In the last week or so, the battery has started losing charge when parked at work. On each of the last three days it has been losing 4% over 10 hours (65% to 61%). The car is left locked with sentry mode off. My phone is also left locked and not touched during the 10 hour period. I've even tried physically switching off the HVAC before leaving the car in case it wasn't turning off when the car was locked - this made no difference. I am at a loss as to what is causing this drain. The only recent change in circumstances I can think off is that I updated the Stats app that I have been using for nearly a year on my phone.

Any ideas before I log the issue with a service centre?

 

[MrBadger]

Any ideas before I log the issue with a service centre?

I would turn off stats app et al before booking service issue. Not only will you find out if it is that, if its not, Tesla won't be able to blame it.

That said, don't have an answer other than to say do double check sentry. I recently found sentry on when it shouldn't have been and cleared the issue by deleting then adding back the location so exclude home/favourites etc could work.

 

[Jason71]

I've had by M3P over just over a year and done 14k miles. In the last week or so, the battery has started losing charge when parked at work. On each of the last three days it has been losing 4% over 10 hours (65% to 61%). The car is left locked with sentry mode off. My phone is also left locked and not touched during the 10 hour period. I've even tried physically switching off the HVAC before leaving the car in case it wasn't turning off when the car was locked - this made no difference. I am at a loss as to what is causing this drain. The only recent change in circumstances I can think off is that I updated the Stats app that I have been using for nearly a year on my phone.

Any ideas before I log the issue with a service centre?

Change your PW. This will invalidate any existing api keys. If this fixes it then re-enable any online services you are using one at a time until you find which it is.

 

[LongRanger]

How many miles to work ? Could be something to do with the drop in temps and the battery management system just feeling less generous ?

It may not be losing charge to that extent, could just be the internal monitoring system being less optimistic given the season change in the last week or so.

However if you can tie the stats app to the point where it started happening that would also be a good port of call. The irony of them is you go looking for problems and when they cause issues the first thing people do is blame the car !

 

[AMP_it_up]

I would turn off stats app et al before booking service issue. Not only will you find out if it is that, if its not, Tesla won't be able to blame it.

That said, don't have an answer other than to say do double check sentry. I recently found sentry on when it shouldn't have been and cleared the issue by deleting then adding back the location so exclude home/favourites etc could work.

I will try turning off Stats over the next few days, although I would be surprised if the app was causing that much battery drain. I've already checked sentry mode is off before leaving the car and is still off when I return, as I am aware it sometimes seems to switch itself on.

 

[AMP_it_up]

How many miles to work ? Could be something to do with the drop in temps and the battery management system just feeling less generous ?

It may not be losing charge to that extent, could just be the internal monitoring system being less optimistic given the season change in the last week or so.

I'm not sure I understand you.

The distance to work is 30 miles. I didn't see such battery % loss last winter in the same circumstances.

However, what I have noticed over the last two evenings when I returned home is that the battery charge has increased by 2% (from 49% to 51%) between me arriving home and going to bed about 3 hours later before the overnight charging started at 12.30 am. I'm wondering if it is a BMS issue?

 

[Glan gluaisne]

FWIW, mine lost 2% overnight a few days ago. Nothing wrong with the car, nothing woke it up. It was just a cold night, so the indicated charge level estimating algorithm was misled. By mid-morning, with the car still parked up, it had gained 2%, as the temperature warmed up.

Worth remembering that the car cannot directly measure the remaining battery state of charge, it has to estimate it, and this estimate is not at all accurate, particularly when the car is just parked up in cold weather.

 

[LongRanger]

From my limited knowledge I would say no issue at all but just the BMS being less and then more generous.

I was interested in distance to work as along the same lines you can cane % remaining in short distances from home when cold to then have a bit return as the car figures stuff out eventually.

For a net 2% in current season and with recent change In temps I would not worry about it at all - unless it suddenly starts swinging wildly.

I charged to 78% this morning, it had dropped to 77 this afternoon when I popped out for a 9 mile round trip then got home at 72. But it’s been 6-12 degrees here today and have to confess to a small squeeze or 2 of throttle on the mountain road nearby. 2 weeks ago I probably would have got home with 74/75%, this just seems to be the behaviour change between 16-18 degrees and current temps.

 

[brkaus]

Our 3 was sleeping less and using more vampire miles right before the 12v battery failed.

I’d disable stats first.

 

[Glan gluaisne]

It's notable that we're getting reports of apparent loss of battery capacity now we're back to getting occasional sub-zero nights again. After around 7 years of driving battery powered cars I'm pretty used to the loss of apparent range and battery charge in cold weather, at a guess I think it's usually around 20% or so loss in winter, compared to summer. Petrol cars are just the same in winter, but it's less noticeable, as the fuel gauge only drops when the car's being driven.

 

[LongRanger]

keep charge level maintained at roughly 50% then only half the electrons are regularly getting cold

 

[LEE3]

Could the car be charging the 12V battery at some point during this period?

 

[Glan gluaisne]

Could the car be charging the 12V battery at some point during this period?

Certainly possible. I've been looking back through data from TeslaMate and there seems to be a pattern developing. Most of the time the car will only wake up when asleep for about ten to fifteen minutes during the night. However, if it's not been used for a couple of days, it will wake up for around two hours. I suspect that two hour wake up is to top up the 12 V battery, makes sense, given that everything runs from the 12 V battery whilst the car is asleep.

 

[darkNstormy]

Change your PW. This will invalidate any existing api keys. If this fixes it then re-enable any online services you are using one at a time until you find which it is.

Agree to try this first. I had an issue recently when my car wouldn't sleep for 2 days. After changing the password it slept within half an hour and no problems since. Have gradually logged in to other apps again and still sleeping.

 

[Jason71]

I will try turning off Stats over the next few days, although I would be surprised if the app was causing that much battery drain. I've already checked sentry mode is off before leaving the car and is still off when I return, as I am aware it sometimes seems to switch itself on.

if stats or something else is keeping the car awake then it will use 200-300wh/h which over 10 hours is between 2000-3000kwh which on an LR or P is between 3-4% of the battery so something keeping the car awake all this time like the stats app could be all that is needed to explain your losses.

 

[AndyF]

I had a similar thing today, was at 22% last night - went out at lunchtime today and it was saying 17%. I don't run any third party apps.

Interestingly, when I went out I went straight to a local charger (BP Polar), when I plugged that in the charger stated the car was at 22%, even though the car was by then saying 16%. Not sure how the charger determines the charge state of the car, and why it would be different to what the car itself is reporting. After about 10 mins charging they had come into sync and were reporting the same battery level.

 

[NorfolkMustard]

The car has a couple of SoC measures. It sounds like it’s giving the Polar charger the higher one and you the lower one.

Currently, mine shows:-

'battery_level' => 64,
'usable_battery_level' => 63,

 

[ElijahEVMan]

My Model 3 charged in the early hours between 12:30 and 4:30 to 85%. It’s been left plugged in all day to my Pod-Point home charger but when I went to drive around 5pm it had dropped to 83%

Sentry mode is disabled whilst at home so I’m not sure why it’s lost so much sitting on my driveway.

I do have a TeslaMate instance running at home but it was my understanding that “shore power” is used for things like that and running climate to precondition the battery prior to departure.

Is this not the case?

On this occasion I just got in the car to drive. Temperature today was about 15c so not exactly cold.

During the day my Pod-Point has a green flashing light that I believe indicates charging is scheduled. Could it be in this state it’s not providing any power to the car?

 

[MrBadger]

Check another time, and you may well find that the 2% has come back.

The behaviour of how SOC is calculated/guessed and/or reported seems to have changed at some point since last winter. Positive and negative swings seem to be quite common now.

 

[NorfolkMustard]

During the day my Pod-Point has a green flashing light that I believe indicates charging is scheduled. Could it be in this state it’s not providing any power to the car?

This sound plausible. If it's withholding power between schedules rather than just waiting for the car to request it, then it's acting like a plug socket switched off.