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HV Battery replaced and now the Drive Unit! (out of warranty)

wk057

Vendor & Senior Tinkerer
Feb 23, 2014
6,006
13,810
Hickory, NC, USA
Have you ever heard of or personally see a drive unit failing with under 5,000 miles? I have a 11/2015 P90D non-ludicrous. Basically throwing all the codes attached and lost most power today and all regen. Car doesn’t have issues charging View attachment 804738
Those errors clearly point to an isolation issue in a component outside of the battery pack. First culprit is usually the battery coolant heater. Next tends to be the drive unit.

As for drive units failing early, sure. My very first Model S required a drive unit replacement at ~3500 miles. Granted, that was a different issue, but still, they can fail at any mileage.

In the case of replacements, a remanufactured unit failing in a short period isn't going to be as uncommon as a new unit... most likely due to a reassembly issue around the inverter coolant seals, which I've seen several times over the years.
 
👋🏻

Without knowing the exact errors originally presented, hard to say what the issue could be.

It's definitely possible the drive unit had an isolation issue that the BMS was reporting. (These usually present as "soft" errors during a drive, things like "Car may not restart"). The 2013 S's, especially early 2013's, are a bit of a mixed bag though.

The vehicle actually shutting down out of the blue would seem to indicate an actual battery issue. Things like a DU isolation issue wouldn't cause a shutdown, just a failure of the car to restart after parking and a shutdown of the HV system at that time.

Guessing you had a 60 pack (based on the replacement being a 75 and your signature saying 40), and the early 60 packs are even more of a mixed bag. Also, as an older 60, you probably had a pretty old revision drive unit (unless replaced at some point after mid 2015)... and those have known issues as well.

Without knowing more, I'd guess a combination of failures is possible.
Normally, from my experience, when the system shuts down and cannot be restarted without an external battery booster after "may not restart" message, the culprit is the drive unit. The reason is the 12v keeps trying to restart the drive until and cause it to drain completely. I've never heard of the system draining the 12v completely when the HV fails.
 
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Reactions: pilotSteve

wk057

Vendor & Senior Tinkerer
Feb 23, 2014
6,006
13,810
Hickory, NC, USA
Normally, from my experience, when the system shuts down and cannot be restarted without an external battery booster after "may not restart" message, the culprit is the drive unit. The reason is the 12v keeps trying to restart the drive until and cause it to drain completely. I've never heard of the system draining the 12v completely when the HV fails.

If the HV system fails for any reason, the DCDC is disengaged. At that point the 12V battery is all that's running anything on the car, and it will die within minutes to hours, depending on what exactly is being run.
 

pilotSteve

Active Member
Jul 14, 2012
1,580
1,528
Prescott Az
Slightly off main topic, but my 12/2016 S90D gave me “replace battery” proactive warning on my app on 11/2021 (5 years of service) so I scheduled amd drove to the Service Center where they replaced it. No problems since then as expected. For me, just waiting for the alert then promptly getting it replaced was perfect.
 
Slightly off main topic, but my 12/2016 S90D gave me “replace battery” proactive warning on my app on 11/2021 (5 years of service) so I scheduled amd drove to the Service Center where they replaced it. No problems since then as expected. For me, just waiting for the alert then promptly getting it replaced was perfect.
True I got a warning too but ignored it because it happened after a rare cold night in San Jose and that is the hardest for a battery. So I am sure the voltage dipped below some threshold and triggered the warning. After the weather warmed back up it did not come back. While the car was in the shop I had them replace the 12v battery.
 
(Another HV battery replacement thread)

My 2013 Model S was working just fine, then suddenly started throwing error codes. I let it sit for about 5 days looking for options. Ultimately I decided to take it in before my appointment to ask for them to help with diagnosing the messages or clearing them so I could continue to drive the vehicle. As I approached the service center, maybe 30ft from the entrance the vehicle completely shut down and that was that.

I was given the new battery replacement option but I pressed them to "look" for a cheaper alternative. The parts catalog seems to default to showing what is in-stock and available. The re-manufactured packs where listed so they called the service department and where told they are around $10,500. I said that is what I wanted. Thanks to other forum members I confirmed that HV batteries replaced at the owners expense have a 4yr or 50000 mile warranty.

I had to leave the car sitting in their lot for over a week before my official service appointment came up. Then they ordered the re-manufactured 75kwh pack and I was told it could take 10 weeks. However just this Friday (after 4 weeks) they got the back and plugged it into the vehicle and told me they needed to run diagnostics and test drive the vehicle on Monday before releasing it.

I just got a message this morning that during the test drive they got more error codes, this time from the drive unit and the rear drive unit might need replacement!!!! They said they are getting the message about reduced power.

It is very suspicious that a functioning battery and a rear drive unit would simultaneously fail. Did they replace the HV battery when the rear drive unit was the culprit? Was there a recent software update (including firmware) that triggered these faults and shut the system down where previous versions it would have been considered fine?

I don't want to be a conspiracy theorist, but I still remember when my MCU1 was blacking out and their first diagnosis said it was caused by the 3G modem so they upgraded it to a 4G modem. Obviously that didn't fix it and it kept randomly crashing so they replaced the whole unit and told me it was the power supply for the display. I questioned them on how a faulty power supply could some times work perfect and other times not and how when it was out the climate control didn't work. Anyway after going round and round they replaced the MCU and eventually we found out it was simply the media card that was causing the crashes.
What do you mean with “media card”? I have also the problem after a trip the mcu1 is crashing/rebooting when I set it in parking mode. My Tegra Board is replace the because they replaced the EMMC for the second time under warranty.
 

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