Vampire discharge

[Slarty1080]

I've just been away for a holiday and on return noticed my M3P had almost completely discharged. I left it with about 240 miles and 10 days later it only had 47 miles. I left it plugged in all the time I was away. It wasn't a problem, but it might have been as I wasn't aware the drain was as much as that.

But it seems odd that it doesn't recharge itself when it gets down to some level? What's the point of leaving it plugged in once its charged? Has anyone else seen this? Not sure it this is a problem or a setting or just normal...

 

[Jason71]

It should have held at the max specified charge level if plugged in.
Drain should also not be that high. You didn't leave sentry mode on did you? Sounds like it was not sleeping

 

[Adopado]

It should have held at the max specified charge level if plugged in.
Drain should also not be that high. You didn't leave sentry mode on did you? Sounds like it was not sleeping

Even with sentry mode on, given that it was plugged in, the charge should have been maintained.

 

[MrBadger]

That scenario and the outcome do not compute...

If it was plugged in and powered, it should have maintained the charge.

Sounds like something was preventing the charge point from supplying power to the car or you had some schedule running.

You don't however say what charge point you were using. If you were using UMC at 10A, and had precondition/climate on, then I could see the car draining as UMC would not keep up with precondition.

 

[Joelly]

That scenario and the outcome do not compute...

If it was plugged in and powered, it should have maintained the charge.

Sounds like something was preventing the charge point from supplying power to the car or you had some schedule running.

You don't however say what charge point you were using. If you were using UMC at 10A, and had precondition/climate on, then I could see the car draining as UMC would not keep up with precondition.

Precondition for 10 days

 

[MrBadger]

yep its a weird one so weird suggestions. Certainly not the normal expected behaviour.

 

[Jason71]

Even with sentry mode on, given that it was plugged in, the charge should have been maintained.

agreed but starting from the premise that it was not drawing any shore power the loss was still too great for it to be sleeping for 10 days surely so it must have been awake much of the time and Sentry is obviously one possible cause of that.

 

[gangzoom]

Something must have been left on to drain that much, our X drops 0.5% SOC each day when left at airport car park. Its currently in Heathrow long stay, parked up with 85% I expect to find it at 80% when we get home after 10 days.

As for charging when plugged in, if the car isn't set to charge every day via scheduled charging than am not sure it would start charging?

I know our car is set to 80% SOC daily but sometimes when I don't unplug the car at the end of day the SOC could have dropped to 78% or lower, if the home charging schedule wasn't set to restart at mid night am not sure if it would restart charging to maintain charge status at 80%?.

 

[pgkevet]

The obvious questions.. was it set for a daily scheduled charge otherwise it'd just charge to a point and stop? Usage options as stated - sentry mode, climate kept on, preconditioning set, something plugged into usb.
My S is at digbeth pending them actually getting around to fixing it. 9 days now and I check daily in hopes that it gets put in service mode. It failed and got towed at 270 miles range and reads 239 at the mo. They obviously pulled sentry mode.

 

[MrBadger]

was it set for a daily scheduled charge otherwise it'd just charge to a point and stop?

I found that after a car stops major charge, if left plugged in, it will do regular short top up charges.

 

[Slarty1080]

Ok so climate was not switched on but sentry mode was. I have 2 USB sticks one for music and one for sentry mode plugged in (surely a USB stick is not going to cause any significant drain is it?). Perhaps there's a setting that I'm not aware of that force it to do regular short charges once it gets below a certain limit?

 

[pgkevet]

Sentry mode explains drainage but doesn't explain why car didn't top up. I haven't noticed my S doing incremental top-ups while plugged in but it would restart a charge every 24 hrs as scheduled when at home. If it was set to do that and didn't then a call to service to check logs (assuming your charger trips didn't go off)

 

[Jason71]

Ok so climate was not switched on but sentry mode was. I have 2 USB sticks one for music and one for sentry mode plugged in (surely a USB stick is not going to cause any significant drain is it?). Perhaps there's a setting that I'm not aware of that force it to do regular short charges once it gets below a certain limit?

Car was never built with sentry mode in mind it was an after thought so when it is on so is the whole FSD computer as a result with sentry mode on the car will not sleep and will use 200wh+ of power which over 10 days that easily accounts for your loss of 200 miles.
So the only remaining question is why it did no keep itself topped up and I don't think anyone is going to be able to answer that since on paper it should have. If you really need to know you may need to run some tests to see if you can replicate it.

 

[gangzoom]

I don't think anyone is going to be able to answer that since on paper it should have.

If the OP hasn't set a daily charging schedule on the car I don't think the car will initiate a charge just because its plugged in.

 

[Adopado]

Ok so climate was not switched on but sentry mode was. I have 2 USB sticks one for music and one for sentry mode plugged in (surely a USB stick is not going to cause any significant drain is it?). Perhaps there's a setting that I'm not aware of that force it to do regular short charges once it gets below a certain limit?

I don't think anybody has asked about your charge point. Does that have settings?

The car can be set to charge at a particular time of day/night, as you probably already know. That should mean that the car will ask for a charge at that time if it is not already at the set percentage.

If the car is plugged in I would have no qualms about checking the app from time to time ... then you can initiate a charge if you need to. In fact just waking the car will make it check it's charge state and top up if necessary. My car did that this morning at 9am even though that isn't its normal scheduled charge time.

 

[Roy W.]

If the OP hasn't set a daily charging schedule on the car I don't think the car will initiate a charge just because its plugged in.

I think you’re right.

 

[MrBadger]

Leaving our Model 3 plugged in unattended results in top up charges. Unlikely that app had been opened to cause these. The main charge had completed at 2:08am during which, part way through we took the 2019.40.50.1 update and car stopped/resumed charge (11 minute outage) as a result

 

[Adopado]

I think you’re right.

We could do with a definitive answer on this one. Mine is set for a 00:30 charge but if I leave it without use, and wake the car by using the app, it will do it's top up (as it did this morning at 09:00). Just to be clear, I didn't use the app to initiate the charge, I just opened the app and closed it without changing anything. Shortly afterwards I received a notification saying the car had charged at 9.00am (a tiny top-up). There must be somebody who has been away with the car plugged in but with no schedule set who can let us know if this does or doesn't affect things.

 

[Andy_T_73]

Leaving our Model 3 plugged in unattended results in top up charges.

Was Sentry mode on?

 

[MrBadger]

Was Sentry mode on?

No - TeslaFi shows the red eye instead of the P icon.