Unplugged Model X for 6 months

[Optic]

I have parked my MX for about 4 months now unplugged (there is no plug at my parking spot). By now the battery should be drained and I will be back in about 1 or 2 months. Does anyone here have any experience on what needs to be done ? (most likely get it towed) Also what kind of damage would there be on the battery if any.

 

[ATPMSD]

Yikes! Worst case, the HV battery may need to be replaced. Talk with Tesla about what to do to give you the best chance at recovering the battery.

 

[Watts_Up]

I have parked my MX for about 4 months now unplugged (there is no plug at my parking spot). By now the battery should be drained and I will be back in about 1 or 2 months. Does anyone here have any experience on what needs to be done ? (most likely get it towed) Also what kind of damage would there be on the battery if any.

Because of COVID, I was not driving my car. I was parked in a garage and I noticed that I was loosing about 3% of battery every month.
Basically the DC/DC inboard charger was charging the 12 V battery every two days for about two hours.

Do you know what state of charge was your battry when you left?

Can you have someone at your residence who could charge time to time your car using a portable charger such as illustrated in this video:

Note: Unless you are in a freezing cold weather, I imagine that the propulsion battery will still have some electrons,
because this battery get isolated using a relay activated by the 12 V battery.

But the 12 V battery would certainly be drained because the DC/DC inverter would not be able to keep it charged.
So I would use first use a 12 V Jump Start charger to get enough 12 V power to get the car alive, such be able to
unlock and open the doors and to be able to have the screen displaying some information or alert messages.

About checking the status of the 12 V battery, I would recommend using a battery monitor App using a bluetooth device.
This would help you to determine if the 12 V battery keep its charge or need to be replaced.

I would also use the OBD2 App Scan My Tesla, which requires an OBD2 transmitter, and may be a special harness
if you don't have an ODBC plug. This would help you to determine if any Cell of the propusion battery get damaged.
I would not trust a Tesla Service Center providing you with such information.

I imagine that there must be some specialised Tesla garages in HK that could help you looking at your car, while you are away,
and may be doing some checks and may be recharging the 12 V battery and even the propulsion battery, as described above.

 

[Watts_Up]

Checking my notes, I reported infact 3% SoC lost after two weeks, so after 4 months you migh have lost 24% and 36% after 6 months.

The only propulsion battery consumption might be to keep the 12 V charged using the DC/DC inboard inverter.
Also sometime the propulsion battery fans and cooling pumps are running.

The 12 V battery was discharged from 13.5 V to 12.5 V mostly because the LTE receiver was on.
This allows accessing the car remotely with the phone App, and allows to get software updates,
Also the 12 V was used by the Bluetooth Low Energy (Bluetooth LE) receivers allowing to open the doors while the car is sleeping.
Otherwise Sentry was off, this is the default setting when you are at home.

I think the major issue will be the 12 V battery which might be drained.
Depending of your model year, this video shows a possible way to open the frunk and to access the 12 V battery:

How to Open Tesla Model X in case Dead battery​

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[Optic]

I let the insurance/license expire as I was not driving it. Tesla just said when I come back, I can get it towed to a super charger, but the tech support does not have any idea on potential HV battery damage. Lots of mention of HV battery damage from draining it, but no one has real anecdotal experience.

 

[Optic]

I am pretty sure the battery is dead or near dead now, since last month I was still getting Tesla app messages about low battery, it has since stopped. And I wouldn't open the Tesla app to wake up the car, in case it uses more charge.

 

[ATPMSD]

I am pretty sure the battery is dead or near dead now

You have two batteries, the 12v and the HV.

It is highly likley the 12v is dead, you will need to use a jumper from a healthy battery (not a charger) to get power to the 12v system. It is unlikely this will wake up the car. However, I *think* the computer should come online as it is on the 12v system, also I would think the windows would open and close.

The Tesla BMS monitors the HV battery and cuts off things as the HV battery SOC drops. It is certainly possible there is some capacity left, even if the SOC was at 0%.

When you jump the 12v battery see if you can open the charging port and if the white light on the port illuminates. If this happens you “should” be able to charge the car. If you cannot charge the HV battery the car probably needs to go to Tesla.

If you can charge the car you should probably get a new 12v battery.

 

[Optic]

yep, So in the end my car was towed to the service centre. The 2 red ropes at the frunk could not be found, so they could not open the hood to jump the 12v. No idea why the rope is missing,. The service center will replace the 12V.

 

[TigerNinety]

Please keep us posted on this. I'm partly thinking about that guy whose Tesla was trapped in Yosemite (?) after the flood.

 

[Optic]

Well, car seems fine after going through service. Still shows 360km in range.