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M3P Drive unit failure?

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Last Tuesday, I pulled into my driveway after a 600 mile trip from Georgia and parked the car short of the garage to get my dog and some items out of the trunk. When I got back into the car, I had a bunch of errors on the car and it wouldn't shift into gear. I was at about 20% battery so I tried to charge, but it wouldn't start charging or even acknowledge the charger.

original_errors.jpg


I went inside for a few minutes and came back outside to more errors. It looked as if the 12V battery was dying on me. I took another photo of the new errors on the screen and about a minute later, the car went black and nothing worked. The 12V battery died.

errors.jpg


Tesla had the vehicle towed the next morning. Figuring out how to get the car working to enable tow mode was an interesting experience. Tesla has had my vehicle since the Wednesday before Christmas and has sent me a few messages back and forth, but still not totally sure what the issue is. They also have a lot of staff out for being sick so who knows when they will get to the bottom of it.

"Initial diagnosis is the High Voltage Pyro Fuse opened on the car. This generally only happens when there is some kind of overcurrent somewhere in the system. We will need to dig further..."

"We need to run some more tests/diagnostics to be sure, but our initial log review leads us to believe it may be drive unit related..."

Also, the fact that Tesla only does Uber credits is very annoying since my town has no uber drivers. The location that I am at for work also has no uber drivers. They only gave the option for uber credits and would not offer any sort of rental or loaner vehicle.

Anyone had these same messages before? I was stopped so I didn't get any of the vehicle shutting down messages. I also did not hear any pops from the pyro fuse before this happened. My car has about 42K in miles. Hopefully, they update the car before I get it back. I am still on FSD Beta 10.5. :(
 
Did they elaborate what that "internal fault" is? Electrical or mechanical?
Sadly they didn't. They said there was some voltage issues and tried to narrow it down between the inverter and the drive unit. Ultimately ended up replacing the drive unit.

For what it's worth, car drove like new after the swap (and my butt dyno made it almost feel faster than it was previously, but that's just anecdotal).
 
Still no update from the service center after nearly three weeks. Uber is not available in my area so I'm stuck bumming rides and what not. Not ideal for sure.

Service center said they had some staffing issues due to the COVID uptick. Hope I get my car back sometime soon. Will update the post when I have a clear answer.
 
Still no update from the service center after nearly three weeks. Uber is not available in my area so I'm stuck bumming rides and what not. Not ideal for sure.

Service center said they had some staffing issues due to the COVID uptick. Hope I get my car back sometime soon. Will update the post when I have a clear answer.
That's messed up. Call them and insist on a loaner. Even if they were temporarily out of loaners, which happens because they never have enough, they should prioritize you for one as soon as any get returned.
 
Vehicle was released from service on Saturday, 23 days after I dropped it off. The replacement parts are listed below. Following the pick up, the drivers window wouldn't roll up completely. The service guy said it was likely due to a calibration issue after the 12V battery died. That was fixed on Monday.

Replaced:
DISCONNECT, BATTERY, PYRO (1064689-00-I) - Fuse - Power Conversion System - HV Battery
ASY, 12V, BATT AND VENT PLUG, M3 (1129182-00-B) - 12V (Lead Acid)
ASY, P-TRAIN, RMN, 3DU-Rear, 840 MOSFET (1521365-00-A) - Drive Unit Rear
 
Vehicle was released from service on Saturday, 23 days after I dropped it off. The replacement parts are listed below. Following the pick up, the drivers window wouldn't roll up completely. The service guy said it was likely due to a calibration issue after the 12V battery died. That was fixed on Monday.

Replaced:
DISCONNECT, BATTERY, PYRO (1064689-00-I) - Fuse - Power Conversion System - HV Battery
ASY, 12V, BATT AND VENT PLUG, M3 (1129182-00-B) - 12V (Lead Acid)
ASY, P-TRAIN, RMN, 3DU-Rear, 840 MOSFET (1521365-00-A) - Drive Unit Rear

I see they replaced the 840 Rear Drive Unit. That's when the 8 Year / 120K mile warranty comes in to cover these issues.
How many miles on your M3P, and which service center in Maryland took care of the replacement?

I'm happy the service worked out for you.