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Drive unit failure with a Lithium LV battery - What you probably didn't know!

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TLLMRRJ

Active Member
Dec 19, 2019
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Houston
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Do you wanna play a game??

Ok, let's play. Guess from the partial list below of cars that I have owned which one is the only car to have left me stranded on the side of the road?

Full disclaimer: I have owned a lot more cars than on this list, but I chose these cars to keep the game as fair as possible since these are the least reliable cars that I have owned.

1965 Jaguar E-Type (owned 6 years, bought used)
1991 Lotus Esprit SE (owned 7 years, bought used)
1991 Lotus Elan M100 (owned 7 years, bought used)
1996 Chevrolet Impala SS (Owned 5 years, bought new)
1998 Lotus Esprit V8 (Owned 10 years, bought used)
1998 Jaguar XJ8 (Owned 4 years, bought used)
1999 Ferrari 355 F1 (Owned 3 years, bought used)
2000 Corvette C5 (Owned 2 years, bought new)
2001 Dodge Viper GTS (Owned 6 years, bought used)
2003 Porsche 911 (Owned 4 years, bought used)
2004 Lamborghini Murcielago V12 gated (Owned 7 years, bought used)
2008 Range Rover Sport V8 (Owned 3 years, bought used)
2011 Jaguar XF (Owned 7 years, bought used)
2014 Range Rover Sport Supercharged (Owned 5 years, bought used)
2023 Tesla Model S (Owned 9 months, bought new)

Bonus question: Which one is the only car that I wish that I had never ever bought?

While you try to figure out the answers to these stumpers, let me tell you a little story: Last week, I was driving my Model S through my neighbor around midnight and as I pulled away from a stop sign in a very relaxed way, I heard the infamous bang! and immediately heard the loud beeping warmings, red graphics on my dash, and lost all forward propulsion. To help describe it better, it felt like what I would image it would feel like if a driveshaft snapped in half on a car while accelerating. Or if you're into airplanes, probably what it feels like if your propeller flew off during your takeoff climb.

There's a lot to say about my experience, but let me just take the opportunity to warn you about one particularly bad Tesla design decision.

My failure is almost certainly a rear drive unit failure. That's what the tow truck drivers were certain it was when I barely mentioned the symptoms, and it's what all of the SC advisors thought without even looking at the car, and what the techs put in the work order, also without even looking at the car. Truth bomb: This happens a lot more than you think. A lot of people post on forums when something bad happens, but a lot more people don't bother to post on icky forums when something bad happens.

So, when the rear drive unit goes, all power from the HV battery is cut off. As you probably already know by now, having 2 or 3 motors doesn't give you redundancy, like Tesla originally claimed on their website, instead, having multiple motors massively increases your statistical possibility that you will be left stranded on the side of the road when one of those motors goes Bang!

Here's the kicker. We all learned to hate the lead acid batteries that Tesla managed to screw up the charging design so that it prematurely kill the batteries, so we all rejoiced when they changed to a Lithium LV battery. But some of us, me included, didn't realize that Tesla engineers/bean counters decided to the put the absolute tiny tiniest smallest capacity Lithium battery that you can imagine in place of that lead acid battery.

What does that mean? When the HV battery is disconnected for any reason, you have about 10 minutes before the car is completely dead, and there's nothing you can do to stop it from dying in 10 mins. And by dead, I mean dead. That includes even the hazard lights, not to mention the doors latches, the windows, the frunk, the trunk, the glovebox, the ability to read the manual on the screen, and ability to put the car in tow mode. EVERYTHING PITCH BLACK!

So keep that in mind when you make your plans for those 10 minutes after your drive unit goes bang! And like a good pilot, always be looking for where you are going to ditch the car when you lose all power. I was very lucky where it happened, but like for some I have read, it put them in an extremely dangerous situation (think fast moving freeway with no emergency shoulder).

I'll give more details of the whole nightmare that isn't even over yet because we are just starting with the incredible service of Tesla, but I wish that I had known what I just told you above. Have it your mind everything you need to do in those 10 minutes to survive wherever you happen to be left stranded.
 
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Have it your mind everything you need to do in those 10 minutes to survive wherever you happen to be left stranded.

I'm gonna guess "What is 2023 Model S LR Red / Cream / 21's (delivered on 12.31.22) Round Steering Wheel for $300, Alex."

Sorry to hear about this and as an owner of a 2023 X LR, I'm going to assume I'm also endowed with the same part.

Bought an S in 2017 and consider myself moderately active on TMC but did not realize rear-drive-unit failures were a sore point beyond normal, garden variety failures.

Curious to hear how this resolves - assuming you're still under warranty?

Also if you have a chance can you ask service if one of those emergency jump start things for ICEs you plug into cigarette lighter ports can do double duty for a Tesla and supply power to the electronics? Might be worth carrying one around to buy a few extra minutes if so.

Edited to add - would something like this (or with a battery instead of a solar panel) be able to supply the low-voltage electrical system with power?
 
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I'm gonna guess "What is 2023 Model S LR Red / Cream / 21's (delivered on 12.31.22) Round Steering Wheel for $300, Alex."

Sorry to hear about this and as an owner of a 2023 X LR, I'm going to assume I'm also endowed with the same part.

Bought an S in 2017 and consider myself moderately active on TMC but did not realize rear-drive-unit failures were a sore point beyond normal, garden variety failures.

Curious to hear how this resolves - assuming you're still under warranty?

Also if you have a chance can you ask service if one of those emergency jump start things for ICEs you plug into cigarette lighter ports can do double duty for a Tesla and supply power to the electronics? Might be worth carrying one around to buy a few extra minutes if so.

Edited to add - would something like this (or with a battery instead of a solar panel) be able to supply the low-voltage electrical system with power?

It might be in warranty. I only have 5K miles and 9 months on the car, so it should be in warranty. But based on my SC experiences so far with this car, I wouldn't be surprised if Tesla denies my warranty on this failure because the air in the tires were .5 psi different from each other.

Yes, you can pop the frunk and put a jumper box by following the more-complicated-than-an-ICE procedure for jumping the car. But it's not completely clear how you power the screen with the computer this way by reading the user manual. Let's just call it what it is, it's a weird design. The battery has a positive and negative connection, but then it has a separate connector mounted on top that goes to the screen and computer. I doubt it would work to plug in the jump box through the cigarette lighter, and seriously doubt you could trust what the bozos at the SC tell you about this matter. Check out the user manual on jumping to see what I mean.

But for packing emergency items for this car, I would take a fully charged jumper box, a set of road flares or battery operated roadside lights so you don't get rear ended, and a set of wheel chocks so you can put the car in tow mode immediately and leave it in tow mode without the car rolling away without being able to use a traditional parking brake.
 
View attachment 973432

Do you wanna play a game??

Ok, let's play. Guess from the partial list below of cars that I have owned which one is the only car to have left me stranded on the side of the road?

Full disclaimer: I have owned a lot more cars than on this list, but I chose these cars to keep the game as fair as possible since these are the least reliable cars that I have owned.

1965 Jaguar E-Type (owned 6 years, bought used)
1991 Lotus Esprit SE (owned 7 years, bought used)
1991 Lotus Elan M100 (owned 7 years, bought used)
1996 Chevrolet Impala SS (Owned 5 years, bought new)
1998 Lotus Esprit V8 (Owned 10 years, bought used)
1998 Jaguar XJ8 (Owned 4 years, bought used)
1999 Ferrari 355 F1 (Owned 3 years, bought used)
2000 Corvette C5 (Owned 2 years, bought new)
2001 Dodge Viper GTS (Owned 6 years, bought used)
2003 Porsche 911 (Owned 4 years, bought used)
2004 Lamborghini Murcielago V12 gated (Owned 7 years, bought used)
2008 Range Rover Sport V8 (Owned 3 years, bought used)
2011 Jaguar XF (Owned 7 years, bought used)
2014 Range Rover Sport Supercharged (Owned 5 years, bought used)
2023 Tesla Model S (Owned 9 months, bought new)

Bonus question: Which one is the only car that I wish that I had never ever bought?

While you try to figure out the answers to these stumpers, let me tell you a little story: Last week, I was driving my Model S through my neighbor around midnight and as I pulled away from a stop sign in a very relaxed way, I heard the infamous bang! and immediately heard the loud beeping warmings, red graphics on my dash, and lost all forward propulsion. To help describe it better, it felt like what I would image it would feel like if a driveshaft snapped in half on a car while accelerating. Or if you're into airplanes, probably what it feels like if your propeller flew off during your takeoff climb.

There's a lot to say about my experience, but let me just take the opportunity to warn you about one particularly bad Tesla design decision.

My failure is almost certainly a rear drive unit failure. That's what the tow truck drivers were certain it was when I barely mentioned the symptoms, and it's what all of the SC advisors thought without even looking at the car, and what the techs put in the work order, also without even looking at the car. Truth bomb: This happens a lot more than you think. A lot of people post on forums when something bad happens, but a lot more people don't bother to post on icky forums when something bad happens.

So, when the rear drive unit goes, all power from the HV battery is cut off. As you probably already know by now, having 2 or 3 motors doesn't give you redundancy, like Tesla originally claimed on their website, instead, having multiple motors massively increases your statistical possibility that you will be left stranded on the side of the road when one of those motors goes Bang!

Here's the kicker. We all learned to hate the lead acid batteries that Tesla managed to screw up the charging design so that it prematurely kill the batteries, so we all rejoiced when they changed to a Lithium LV battery. But some of us, me included, didn't realize that Tesla engineers/bean counters decided to the put the absolute tiny tiniest smallest capacity Lithium battery that you can imagine in place of that lead acid battery.

What does that mean? When the HV battery is disconnected for any reason, you have about 10 minutes before the car is completely dead, and there's nothing you can do to stop it from dying in 10 mins. And by dead, I mean dead. That includes even the hazard lights, not to mention the doors latches, the windows, the frunk, the trunk, the glovebox, the ability to read the manual on the screen, and ability to put the car in tow mode. EVERYTHING PITCH BLACK!

So keep that in mind when you make your plans for those 10 minutes after your drive unit goes bang! And like a good pilot, always be looking for where you are going to ditch the car when you lose all power. I was very lucky where it happened, but like for some I have read, it put them in an extremely dangerous situation (think fast moving freeway with no emergency shoulder).

I'll give more details of the whole nightmare that isn't even over yet because we are just starting with the incredible service of Tesla, but I wish that I had known what I just told you above. Have it your mind everything you need to do in those 10 minutes to survive wherever you happen to be left stranded.
Just happened to me last week. I was told the system read a controller was missing. I didn't get a 10 minutes warning. I received a 1 second warning and the car stopped dead on the middle of the interstate.
They need to install a true warning system so people know when something about to fail.
 
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Just happened to me last week. I was told the system read a controller was missing. I didn't get a 10 minutes warning. I received a 1 second warning and the car stopped dead on the middle of the interstate.
They need to install a true warning system so people know when something about to fail.

My longer rambling might have confused things here. My car did not give a warning of all forward propulsion failing. It just did that without any warning and then told me it had a major failure right away.

What I got a warning about was the entire car going dark because the low voltage power was low. It did not give any time frame, and I would never have imagined that the LV battery would be designed to only last 10-15 minutes. What a bunch of buffoons designing cars at Tesla!
 
Sorry to hear of the failure. I'm sure while most ICE owners have not had a timing chain break, cracked head, or blown piston, they do happen causing the car to immediately stop. It's unlucky that the first catastrophic failure you've encountered happened with your EV. Most EV owners have no problems with the motors for the life of the car.

Should the HV motor/inverter short out (on any EV, not just Tesla), the HV will disconnect to protect the HV battery. Now there are a number of ways an electric motor can fail (just a lot fewer than an ICE engine failures). The motor could have a mechanical failure, an open, or a few other situations in which the car doesn't need to disconnect the HV. Some of these motor failure conditions allow for an alternate motor to continue to operate the vehicle (those that have more than one motor), unlike ICE cars, where you are dead in the water should the engine fail.
 
Sorry to hear of the failure. I'm sure while most ICE owners have not had a timing chain break, cracked head, or blown piston, they do happen causing the car to immediately stop. It's unlucky that the first catastrophic failure you've encountered happened with your EV. Most EV owners have no problems with the motors for the life of the car.

Should the HV motor/inverter short out (on any EV, not just Tesla), the HV will disconnect to protect the HV battery. Now there are a number of ways an electric motor can fail (just a lot fewer than an ICE engine failures). The motor could have a mechanical failure, an open, or a few other situations in which the car doesn't need to disconnect the HV. Some of these motor failure conditions allow for an alternate motor to continue to operate the vehicle (those that have more than one motor), unlike ICE cars, where you are dead in the water should the engine fail.

How many posts have you seen where those failures happen on a new ICE car with only 5K miles?? I can point you to many posts on this forum for Tesla's. And there are a lot less Tesla's on the road than ICE cars.

Stop with the lies!

Should an inverter/motor short out, that should only cut the power to that inverter/motor. You don't know what you are talking about. Stop making apologies for poor design choices that trade your safety and convenience for a few pennies saved for Tesla.
 
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Just happened to me last week. I was told the system read a controller was missing. I didn't get a 10 minutes warning. I received a 1 second warning and the car stopped dead on the middle of the interstate.
They need to install a true warning system so people know when something about to fail.

I just filed a safety complaint case with the NHTSA because a new car that just loses all propulsion on the road is a major safety issue and on top of it, losing all power to the entire car within 10-15 minutes, so even the safety hazards lights don't work, makes this a much bigger safety issue when someone rams into the back of the stalled out car.

Fanboys want to gas light owners that have had this failure and play whataboutism to sweep it under the rug, but screw them. Everyone that experiences these failures should report it directly to the NHTSA so the design can be investigated. I can promise you, Tesla made a cost cutting decision with their designs that caused this safety issue.

It's very quick and easy to report the failure here, and you will get a tracking link to see the progress: