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

[wk057]

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.

 

[silverp85+]

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.

 

[wk057]

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.

 

[silverp85+]

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.

Agreed. The time of 12v battery death definitely differs. When my rear DU failed the 12v died in 1 minute or less.

 

[boilerbots]

Mine did the same but the 12V battery was probably 4yr old. When Tesla hooked their jumper pack to the car it started smoking and smelled like rotten eggs. The guy said it has the same battery inside the jumper that is used in the car and they need to be replaced every few years.

 

[pilotSteve]

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.

 

[boilerbots]

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.

 

[tesluv108]

Tesla diagnosed this as a battery coolant heater. We will see if this is the only problem after I get it back.

 

[Myfirstone]

(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.

 

[pacof]

There have been a lot of messages back and forth with the service representative where I felt like I had to guide them through the repair process. I kept asking them to diagnose the root of the faults and stop "swapping" parts.

They replaced the rear drive unit because of the DU Isolation problem and ultimately swapped by original HV battery back in the vehicle. Then they said that they fixed an issue with the battery with a "software update". They instructed me to drive the vehicle and cycle the battery and the BMS will be adjusting the capacity over the next few weeks.

To bad I will never know what really happened or what the root cause of any of this is. Why the drive units develop isolation faults and how much it would really cost to repair. I was sold a re-manufactured drive unit for $4800 and they probably will take my drive unit, clean it up and repair the isolation fault with only a few hours labor and sell it to someone else.

My total repair bill went from around $13,000 down to $6,000 so half but still expensive compared to any traditional automobile.

Now I hope the battery holds up for a few more years.

Very curious about the "software update" - did they tell you what that supposedly fixed? I have a Model S 2013 40kWh; we replaced the 3G modem with a 4g LTE upgrade, but then the memory module failed (supposedly) and with that cost, we just went ahead and updated the entire screen display (since the glue was separating from the screen, rendering the touch screen difficult to use), and then when we picked up the car after that repair, the car was unable to charge. No errors ever reported to me. Now, they say a battery cell is bad and have to replace the entire battery unit (sounds like a similar problem you experienced) and have to pay $13,000. I'm very suspicious as well and was looking through the logs with the service manager. "Low voltage on one of the battery cells" - have you heard of that and is that really the cause to replace the entire battery unit? I firmly believe the screen replacement combined with updated software is causing the problem, but cannot prove it. I've had the car for 9.5 years and NEVER had a charging problem with the car. Very, very suspicious.

 

[wk057]

The 2012 + 2013's are having battery issues left and right. I have over a dozen customer vehicles from 2012-2013 in the shop at the moment for battery replacements/repairs. We're completely swamped.

The issue is almost always one of two things: a bad cell group (meaning the pack needs replacement), or moisture ingress somewhere near the front/center of the pack causing a sense wire to dislodge (copper/aluminum ultrasonic welds hate moisture).

 

[glide]

The 2012 + 2013's are having battery issues left and right. I have over a dozen customer vehicles from 2012-2013 in the shop at the moment for battery replacements/repairs. We're completely swamped.

The issue is almost always one of two things: a bad cell group (meaning the pack needs replacement), or moisture ingress somewhere near the front/center of the pack causing a sense wire to dislodge (copper/aluminum ultrasonic welds hate moisture).

Impossible. Tesla batteries last FORVER. A Billion miles even.

Only ICE vehicles require expensive repairs.

/s

 

[ddb1001]

But…but…Tesla’s always just work! They have million-mile batteries.

Only ICE vehicles break down and have repair costs.

LOL .. you don't hear this anymore.
Now the narrative has changed to, "What do you expect from an old battery pack made by a startup?"

 

[vcor]

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.

Jumping ahead of the user's response, I think he means his personally attached USB drive was the cause of all the problems. For example, problems can occur if you have a damaged USB drive, a boot virus on the drive, a counterfeit drive (lots of those around), or a painfully slow drive. I suspect that's one reason Tesla now includes a USB drive with each new car to reduce the headaches caused by users and bad drives.

 

[Dave EV]

Jumping ahead of the user's response, I think he means his personally attached USB drive was the cause of all the problems. For example, problems can occur if you have a damaged USB drive, a boot virus on the drive, a counterfeit drive (lots of those around), or a painfully slow drive. I suspect that's one reason Tesla now includes a USB drive with each new car to reduce the headaches caused by users and bad drives.

I've seen flaky/bad USB devices cause all sorts of weird issues on Windows/Linux PCs, so no real surprise that they can issues on Teslas as well.

 

[vcor]

Also while a boot virus on a USB drive will screw up the Tesla boot, it will not be infected by it. The good news is it's easy to fix by removal of the USB drive.