Not a Model 3, but my 2023 Model S LR with only 5K miles just catastrophically failed, and I am pissed about it. It's a new $100K car, and like others have said on here, I have own so many cars over the last 40 years, and there have been plenty of repairs needed as they became old cars, but literally none of them left me stranded on the side of the road.
In my case, the rear inverter failed and blew the pyro fuse. It sounds like a gun shot going off inside the bowels of the car, because it is basically a gun shot going off, to cut all high voltage power from the battery to any part of the car.
Why I am so angry? Because I got stranded on the side of the road at midnight? Because Tesla sent the wrong tow truck the first time that couldn't tow a bricked car even though Roadside support knew the situation, and then when I called back they tried to get me to pay for the correct tow truck? Yeah, sure, I am ticked about those things big time.
But what really ticks me off is being an electrical engineer and a lifelong car nut, so I realize that Tesla made some very pathetic and dangerous design issues to save a few pennies at the expense of our, and our family's, safety.
I have 2 drive units, so if one drive unit goes bad, I should be able to continue on the good one. But Tesla made the decision to blow the main high voltage battery fuse when one of the drive units goes bad. Could they have separated out the circuits? Sure. If you run a space heater and a hair dryer on the same outlet in your house, you don't blow the breaker for the power to the entire neighborhood. Same concept applies. But 1 breaker is cheaper than 2, right?
When the HV battery is disconnected, you will not only not able to drive, but your cozy little life support capsule will die very soon running off the low voltage battery. Within a matter of time, you won't have any A/C, you won't be able to charge your phone, won't be able to look at the manual on the screen to see how to handle a breakdown, you won't be able to open any doors, open any windows, trunks, gloveboxes, you won't have any lights inside or outside, including the safety hazard lights so you don't get rear ended, and you won't be able to put the car in tow mode.
Then Tesla made another incredibly bonehead decision to save themselves a few dollars. They got rid of the lead acid battery because they couldn't figure out how to design a charging circuit for it that doesn't cause the batteries to fail prematurely after only a couple of years, instead of 4-7 years like ICE cars. So they replaced the lead acid with a lithium ion battery. Sounds great? Yeah, not until you realize that this amazing new battery has about 1/7 the capacity of the lead acid battery. What does that mean? Now instead of having a couple of hours of power to critical safety systems, like the hazard lights, and functionality such as tow mode, you have around 10-15 mins. By the way, the lithium batteries can and do fail, but instead of $85 for the lead acid battery, that pathetic little battery that is pretty useless, will cost you $200 out of warranty.
When was the last time you called a tow truck for a breakdown and they showed up in 10-15 mins? If there's an accident on the freeway, there's a dozen of them lined up before 1st responders even get there, but for a breakdown, you're doing really well if it's 2 hours, and probably a lot longer, especially if you are far out of town and/or at night.
So be ready for your inverter failure. You have to hope you can pull over safely where ever it decides to happen, and you have 10-15 mins to collect your thoughts and execute everything you need to do to survive that breakdown in whatever situation Tesla put you in before the entire car goes dark.
And if you own a rear drive Model 3, you are the smart one here. You statistically have the least chance of being left stranded. Did you spend more money with Tesla for a dual motor? Well, you screw yourself. You doubled your chances of being left stranded, when you probably thought you were buying fool-proof redundancy. I mean, what's the likelihood of both motors failing at the exact same time, right? Yes, it's next to nil. But if you paid the big bucks for a tri-motor Model S/X, you now have 3 times the chance to be left stranded than the cheapest Tesla. And if they make a 4 motor Cybertruck, you must have a death wish to buy it.