Shut down with supercharger in sight

[David99]

It was bound to happen to me. For years I was bragging that I regularly drive my car down to single digits and it has never shut down. Now it finally did. And to punish me a little extra for my big mouth, it happened at 3:30 am just before the exit for the supercharger. I could literally see it. There goes the theory that the car will allow you to go a little extra if you are heading to a charger.

It was totally my own fault. I was pulling a trailer and my energy consumption was about double. At higher discharge rates the voltage drops faster and earlier at the end. I had 1 mile left when it shut down.

A few things to keep in mind when that happens:
Pull over as soon as you can. You have 5-10 seconds from the message popping up to loosing all motor power.

Since the 12 Volt battery isn't charged any more, get out of the car and let it be. This is your best bet to keep the 12 Volt battery alive until the tow truck arrives. Roll down the windows. When the 12 Volt battery dies opening or closing the door can break the windows.

Remember 'tow mode' is under the service tab.

Always have one of those external battery chargers for your phone. You are going to make many calls and do a lot of Googleing to find nearby chargers, and take lots of pictures and videos of your adventure LOL

The tow attachment thingy that came with my car is under the carpet in the frunk and you have to take the nose cone off to attach it. Just to mess with you when you are already stressed out, Tesla used a left tightening thread on it. WTF? I recommend making yourself familiar with your car and how it works so you know what to do in the situation.

One of those compact jump start battery packs can be a life saver. If you have to wait very long and the 12 Volt battery dies on you, you can't even plug in to charge the car. You first have to bring the 12 Volt system alive. One of those little batteries will do the job.

Always have a jacket and extra cloths in your car. Prepared as I am I was in my flip flops and shorts coming from California and freezing my butt off waiting at night in Iowa.

I wish Tesla would give the driver a little more time before cutting off power. The time you have might not be enough on a busy freeway and find a safe place to stop. There is zero heads up. I had ScanMyTesla app running and couldn't see any indicator that would have given a hit. The only thing that gives you some idea is the power limiter. If it's down to 80 kW, you are very close to a shut down. In general it helps a lot to drive very carefully and gentle when the battery is very low. By driving super careful I was able to get to 0 % without a shut down countless times. In this case, I didn't pay attention and kept driving at normal speed. With the trailer that was 60-80 kW.

 

[ewoodrick]

I could have sworn that your car has a gauge that indicates the % or miles remaining and then when it gets low, changes colors. I think that there is a pop-up and if you are navigating, a number of indications that you aren't going to reach the charger.

But since you may be talking about a notification on the 12V battery, I believe that you should safely assume that you are running on borrowed time when the main battery dies, since it hasn't charged the 12V battery in a while.

Oh, and if you killed the 12V battery, might as well go ahead and replace it.

 

[beatle]

Lots of good advice here. Thanks for posting. Hope it doesn't happen to me!

 

[David99]

I could have sworn that your car has a gauge that indicates the % or miles remaining and then when it gets low, changes colors. I think that there is a pop-up and if you are navigating, a number of indications that you aren't going to reach the charger.

But since you may be talking about a notification on the 12V battery, I believe that you should safely assume that you are running on borrowed time when the main battery dies, since it hasn't charged the 12V battery in a while.

Oh, and if you killed the 12V battery, might as well go ahead and replace it.

Tesla sure gives you plenty of indicators that you are running low. As I said I was not paying attention, so it's my fault. I just wish when it shots down it would give you more than a few seconds. It can get dangerous. But then the same happens when any car runs out of fuel or energy.

The 12 Battery is a deep cycle type. It will most likely survive if it's not too long ( a few hours).

 

[NoMoGas]

Tesla sure gives you plenty of indicators that you are running low. As I said I was not paying attention, so it's my fault. I just wish when it shots down it would give you more than a few seconds. It can get dangerous. But then the same happens when any car runs out of fuel or energy.

The 12 Battery is a deep cycle type. It will most likely survive if it's not too long ( a few hours).

Been there... twice. It sucks but yep, totally my fault. Both times I was IN the lot where the SC was. LOL

 

[doghousePVD]

It didn’t warn you? The gauge goes yellow, then red, and are annoyed that on a 300 mile range vehicle it may be off by a few hundred yards?

It also flashes warnings that you won’t make your destination. What more can the car do?

 

[kingkong5]

What did you end up doing? Push the car to the supercharger somehow?

 

[ucmndd]

It didn’t warn you? The gauge goes yellow, then red, and are annoyed that on a 300 mile range vehicle it may be off by a few hundred yards?

It also flashes warnings that you won’t make your destination. What more can the car do?

What part of the repeated “it’s my fault, the car gives you plenty of warning” statements were you confused by?

 

[heems]

What part of the repeated “it’s my fault, the car gives you plenty of warning” statements were you confused by?

By the part “I just wish when it shots down it would give you more than a few seconds.”. If it gave 2 minutes then he’d abuse that and make another thread post and we go in circles. The guy ran the thing out of juice. No need to say “I wish ... “ imho. Just stick to “I efd up.”

 

[cduzz]

By the part “I just wish when it shots down it would give you more than a few seconds.”. If it gave 2 minutes then he’d abuse that and make another thread post and we go in circles. The guy ran the thing out of juice. No need to say “I wish ... “ imho. Just stick to “I efd up.”

Possibly the car doesn't actually know exactly where the bottom is until it asks for power and doesn't get it, at which point it is too late. When doing some work at a machine tool factory I stepped on the top of a suspended ceiling (and went through, down onto the conference table 6 feet below)

I've never ventured to the bottom of my car's range (10% is as low as I trust) -- it would be nice if it really aggressively limits power output. 15-25 mph for the last 5 miles is better than 65 for the last 1 mile then 0mph for the remaining 4. Only the most adventure seeking among us would intentionally venture into that punishment room. It is probably slightly hazardous to have the car limit speed to 20 mph, but it is also hazardous to just shut off.

I'm sure many meetings took place at Tesla to discuss how to deal with this; we don't get the minutes to those meetings, just the deliverable...

 

[ohmman]

@David99, I know you said you weren't paying attention, so this tip may not help, but I once was pretty tight en route to a Supercharger and decided to drop my trailer a few miles away from the charger, go charge, and come back to pick it back up. Having the car untethered on that last leg made it possible for me to make it.

If nothing else, a tip for others that are pulling a load in the future.

 

[Bill_75D]

Do the hazard lights work from the 12v battery, or are you sitting on the side of the road totally dark?

 

[Rocky_H]

I would prefer the car to reduce power if necessary ahead of time if there is danger that is won't make it to 0. This way it will make it to 0 as 'promised' without compromising range. That's what I do using my foot and it helped me getting beyond 0 a few times.

I've driven my car down to 1% or 0% many times. Several times even below 0%. I actually aim for 5% or lower on road trips to save time at Superchargers. The key thing when the battery is low is to drive gently. Use the accelerator very carefully, keep the speed low, accelerate very carefully. If you push it hard the car will shut down much more likely.

There is a chance it will, but more times than not it will continue to go for a little more. It depends on a lot of things, but having zero miles left on the estimate does not always mean the car will shut down. Many many examples where it did not.

The algorithm can be a little off especially when partially charge and discharging the battery. The car will always estimate on the lower side to be safe. That's why often you can go a little beyond zero. It's not a buffer, it's just a margin of error that is most of the time on your side.

Wow--it finally caught up with you. I do respect that you posted about it when you got caught.

 

[hmgolds]

First, thanks for posting this. We don't often like to go public with embarrassing moments, but it does help others.

I keep a hard copy of the tow instructions in the glove box. I figure a) its accessible if the mcu is down and b) easier to refer to if stranded. But your post reminded me that I might not be able to open the glovebox if mcu is down. I suppose I should store on my phone also.

Similar issue with your jump start battery suggestion. If your 12v is dead, how do you open the frunk to get to the 12v battery? I understand there is a way to "hack" this, but still requires an external battery.

As to your flip flops and shorts, we see that often in Minnesota with people arriving from warm locations who find themselves unexpectedly waiting outside for any number of reasons. If non-Minnesotans, it provokes some sympathy. If it happens to Minnesotans, it provides endless entertainment.

 

[Ostrichsak]

FWIW we have a similar story from just a few weeks ago. We ran out 7.6 miles from the scheduled Supercharger with 13 miles of range remaining.

Although I've seen the warnings to lower speed to reach destination many times over the tens of thousands of miles of road trips we've taken this time there was none. Not one warning. We thought we were good to go with 2x the range required to make it (even though it was cutting closer than I would have liked) and then there was a sudden loss of power w/o any warning prior. I looked down and the vehicle was decelerating with the message to pull safely out of traffic as the car was powering off. This was our first indication that something was wrong after it was done.

In our case, there were no exits along the stretch of I70 we were on and there was a slight curve before where our car came to rest and no real shoulder to speak of. We were out of the lanes of traffic but only barely. I wasn't super comfortable with where our car was located and really wish we had more time to find an exit. When I called Tesla Roadside they admitted some sort of failure caused it and said a tow truck would be over 2.5 hours away. I said I wasn't comfortable with the car where it was for that extended period and he suggested calling local law enforcement who had access to different tow companies who might be able to get there quicker. A 5min phone call to them and being conferenced in with the first tow company on her list and we had a flat bed there 20 minutes later. Also a poor time to discover that the previous owner didn't have the tow hook in the car. My bad for not checking when I bought it but I learned a valuable lesson that day. I went ahead and made sure all cars had them.

I read online and saw videos where some claimed there was a secret amount of juice much like most ICE cars in case you did hit zero. Fortunately we've never come even close to testing that theory first hand. I'm seeing more and more first-hand accounts like ours though so this is troubling.

 

[Darmie]

Thanks for the post. You all make good points on how to handle this and I will consider keeping a few things in my trunk bag.
1, Small lipo 12v jump pack
2. Small Phone charging bank
3. Tow hook in the back of car not front.

 

[croman]

Been down to 1 mile before. Was nerve wracking. Sorry you didn't make it. I was down to below 50kw power based on dashes. I babied the accelerator and tried not to brake and it took forever to even start supercharging.

 

[ohmman]

As to your flip flops and shorts, we see that often in Minnesota with people arriving from warm locations who find themselves unexpectedly waiting outside for any number of reasons. If non-Minnesotans, it provokes some sympathy. If it happens to Minnesotans, it provides endless entertainment.

Back in my younger days, I flew from Texas to Minneapolis in winter for an overnight work trip. I did not own a heavy coat, so I wore my leather jacket. When I arrived at the rental counter, the young men there were looking at each other and grinning. They handed me the keys to the farthest car away, which was covered in ice and snow and unable to be opened. It was well below 0 and I was freezing. I ran back in and asked for another car. I could hear them laughing in the back...

I have to admit, it was a pretty good prank to play on a fool that didn't come dressed properly.

 

[David99]

Do the hazard lights work from the 12v battery, or are you sitting on the side of the road totally dark?

Yes the 12 Volt battery will power everything except main motor and HVAC. The hazard lights will drain the 12 Volt battery pretty quickly, though

 

[David99]

@David99, I know you said you weren't paying attention, so this tip may not help, but I once was pretty tight en route to a Supercharger and decided to drop my trailer a few miles away from the charger, go charge, and come back to pick it back up. Having the car untethered on that last leg made it possible for me to make it.

That's a good idea. I will keep that in mind as an option if it really gets close.