That very loud and painful "clunk"

[Kraken]

Here are some questions I have after seeing these:
Has a refurbished A pack failed?
does a refurbished A do 120kw charging?

if so, maybe the A packs are being upgraded and fixed when refurbished.... Maybe that's part of teslas lack of concern about them... Eventually they will all fail and the be fixed. Maybe they are basically B packs after, but they don't relabel them.

Has a B battery failed like this?

I'm not concerned about the failure, because any car could fail like this, and their customer support in these situations has been spectacular. I'm mainly concerned about their handling of failed packs.

 

[FlasherZ]

Here are some questions I have after seeing these:
Has a refurbished A pack failed?
does a refurbished A do 120kw charging?

if so, maybe the A packs are being upgraded and fixed when refurbished.... Maybe that's part of teslas lack of concern about them... Eventually they will all fail and the be fixed. Maybe they are basically B packs after, but they don't relabel them.

Has a B battery failed like this?

I'm not concerned about the failure, because any car could fail like this, and their customer support in these situations has been spectacular. I'm mainly concerned about their handling of failed packs.

I don't want to speculate just yet. It's not completely clear that the battery pack is at fault here. From what I read from other owners, it seems that when these symptoms occur, it's a drive unit failure. In some cases, batteries are replaced, in others they are not. For all we know the failure could be exclusively early drive units, and the correlation with "A" battery packs is purely a result of the production date of the units. Tomorrow I should have more details.

 

[Kraken]

I don't want to speculate just yet. It's not completely clear that the battery pack is at fault here. From what I read from other owners, it seems that when these symptoms occur, it's a drive unit failure. In some cases, batteries are replaced, in others they are not. For all we know the failure could be exclusively early drive units, and the correlation with "A" battery packs is purely a result of the production date of the units. Tomorrow I should have more details.

Fair enough... And to answer my own question. One guy said he had similar issues and a battery replacement who got his car in June. I got mine in mid June, and all this discussion finally got me to check. It is a B battery as I expected.id expect his was a B battery as well.

 

[JRP3]

Might be worth trying to clarify what a pack "failure" could be. I'll assume that Tesla uses contactors between series groups of cells so that the pack is broken up into lower voltage groups in an accident. If one of those contactors fails and opens up during operation all power flow stops, though all the cells are still perfectly fine. On the other hand none of the pictures or diagrams I've seen show these contactors, so my assumption could be wrong.

 

[FlasherZ]

Might be worth trying to clarify what a pack "failure" could be. I'll assume that Tesla uses contactors between series groups of cells so that the pack is broken up into lower voltage groups in an accident. If one of those contactors fails and opens up during operation all power flow stops, though all the cells are still perfectly fine. On the other hand none of the pictures or diagrams I've seen show these contactors, so my assumption could be wrong.

I believe that fused links provide that protection between cells and strings inside the battery pack and that a "pyro" fuse and set of contactors will protect everything external to the battery pack in such a failure scenario.

 

[efusco]

This thread has my attention now...
This morning, while decelerating (no or little friction brake), just as I came to a stop I heard more than felt a 'thunk' in the back of the car. It sounded kind of like a bowling ball had rolled forward and hit the back of the back seat as I stopped...but I didn't have any bowling balls or bowling-ball like objects to roll forward and hit anything...so that struck me as odd, but the car continued to operate WNL and has for the last 5 miles or so. Probably mine is totally unrelated, but having a production number close to yours (VIN 1267) it certainly makes me feel a bit more concerned...

Will report back, obviously, if anything similar occurs.

 

[walla2]

Here are some questions I have after seeing these:
Has a refurbished A pack failed?
does a refurbished A do 120kw charging?

I'm not concerned about the failure, because any car could fail like this, and their customer support in these situations has been spectacular. I'm mainly concerned about their handling of failed packs.

Someone here reported their refurbished A pack being 90 kW limited. I will eventually try mine out.

I may also be the first to receive a lower SOC refurbished pack. Still trying to balance (havent driven for 3 days) and do some 100-20% drains to see if this is true as Tesla has recommended.

 

[dave]

This thread has my attention now...
This morning, while decelerating (no or little friction brake), just as I came to a stop I heard more than felt a 'thunk' in the back of the car. It sounded kind of like a bowling ball had rolled forward and hit the back of the back seat as I stopped...but I didn't have any bowling balls or bowling-ball like objects to roll forward and hit anything...so that struck me as odd, but the car continued to operate WNL and has for the last 5 miles or so. Probably mine is totally unrelated, but having a production number close to yours (VIN 1267) it certainly makes me feel a bit more concerned...

Will report back, obviously, if anything similar occurs.

This is exactly what I experienced a couple days ago. I'm slightly concerned, because it wasn't a normal sound and I can't explain what it was -and I have a long road trip planned next week. I'm VIN 3236 - still a 2012 car. Definitely let us know if you experience it again.

 

[FlasherZ]

I was informed by the service center that engineering has analyzed the logs and have concluded the HV battery pack must be replaced. No other details (pack type, etc.) More to come, I should have the car back later today or early tomorrow, depending upon how the replacement goes and if it implicates anything further.

 

[JRP3]

I believe that fused links provide that protection between cells and strings inside the battery pack and that a "pyro" fuse and set of contactors will protect everything external to the battery pack in such a failure scenario.

Could be, but after an accident the fused links might not fail if they aren't exposed to elevated current levels, and normal current levels in a damaged pack could still cause issues. I would expect an inertia switch being triggered on a strong enough impact that then disconnects the contactors and breaks the pack into smaller voltage modules, but maybe they didn't do that.

 

[AmpedRealtor]

I wonder if the reason Tesla is not addressing the battery A/B issue, as discussed in another thread, has to do with the fact that Tesla knows something is wrong with the A battery and understands that it will probably replace most of them under warranty. However, given the high cost of the battery, they are addressing the issues as they occur. Tin foil hat time? LOL

 

[FlasherZ]

Could be, but after an accident the fused links might not fail if they aren't exposed to elevated current levels, and normal current levels in a damaged pack could still cause issues. I would expect an inertia switch being triggered on a strong enough impact that then disconnects the contactors and breaks the pack into smaller voltage modules, but maybe they didn't do that.

I don't know if that's really required. If the battery pack is contained even after an accident, and the pyro fuse blows or the contactors are open, the risk is effectively contained. If there is a compromise of the battery pack and it starts a chain reaction - either short-circuit or some other mean, it should blow other fusible links. Sometimes too much resiliency creates more complexity and less reliability -- I recall a network equipment vendor where a recurring joke was "how do you increase resiliency of your network? pull the resiliency processor", because the complexity of making the modules back each other up was a bigger problem than managing a self-healing network.

 

[FlasherZ]

This thread has my attention now...
This morning, while decelerating (no or little friction brake), just as I came to a stop I heard more than felt a 'thunk' in the back of the car. It sounded kind of like a bowling ball had rolled forward and hit the back of the back seat as I stopped...but I didn't have any bowling balls or bowling-ball like objects to roll forward and hit anything...so that struck me as odd, but the car continued to operate WNL and has for the last 5 miles or so. Probably mine is totally unrelated, but having a production number close to yours (VIN 1267) it certainly makes me feel a bit more concerned...

For what it is worth, my shutdown occurred at acceleration from a red light, in both cases. It was between 80-120 kW of power where it gave the definitive "thunk". In both cases, immediately the gear selector turned red and the triple-bong alerts started coming forth. Not sure what you might have experienced, Evan, but yours happening on a stop (no regen/no power consumption) is different and having no alerts come from it seems strange.

 

[andrewket]

I wonder if the reason Tesla is not addressing the battery A/B issue, as discussed in another thread, has to do with the fact that Tesla knows something is wrong with the A battery and understands that it will probably replace most of them under warranty. However, given the high cost of the battery, they are addressing the issues as they occur. Tin foil hat time? LOL

If that were the case then the best thing they could have done is offer to replace the packs due to charging rate and customer concern. If you're going to eat the cost anyway, might as well get a PR/customer loyalty benefit.

 

[FlasherZ]

If that were the case then the best thing they could have done is offer to replace the packs due to charging rate and customer concern. If you're going to eat the cost anyway, might as well get a PR/customer loyalty benefit.

3,500 cars * $30,000 (VERY VERY rough) is >$100M. Not exactly an easy offer to swallow in a short period of time. If you want to take the tinfoil hat approach, I'd find it much more palatable to spread it out as failures occur rather than to make an offer and see northward of 2,500 cars all want this RIGHT F'N NOW (just look at the screaming about a 1-month delay in returning the 'low' suspension setting, and that's on a promised/documented feature vs. the at-the-time undocumented higher charging rate on B packs).

I don't believe that's the case, by the way. The sample / report size is small here, and we don't know exactly what the occurrence is. So let's not draw crazy conclusions.

 

[Discoducky]

I'd bet that it is something simple in the pack and that TM is getting some great FA out of these packs and putting them back into service after reconditioned.

Hope you get a nice new pack though FlasherZ!

 

[beegee]

I was informed by the service center that engineering has analyzed the logs and have concluded the HV battery pack must be replaced. No other details (pack type, etc.) More to come, I should have the car back later today or early tomorrow, depending upon how the replacement goes and if it implicates anything further.

Hopefully you get the newer pack fwiw- at least I got to put a few extra miles on my new car!:biggrin:

 

[NigelM]

You'll know it... this one is a major clunk followed by all sorts of bells and whistles going off... and it's unlikely to happen while just sitting there (although I suppose it could happen...)

Yeah, it can happen just sitting there. Happened to me while parked on Sunday afternoon (no clunk or similar sounds), got in the car and immediately saw all the warnings Flasher had and the car wouldn't go into drive. Tesla service was awesome and the car got flatbedded to Tampa. Received news this afternoon that they replaced the main battery pack and dealt with some other bits, the car is being delivered back to me tomorrow morning.

Early Sig VIN but apart from some early door handle issues and ambient lights buzzing it's been largely problem free the last 18 months.

 

[tezco]

If this happens to Bill, Rick, Jerry and Bonnie we'll have to start a conspiracy thread.

 

[apacheguy]

Yeah, it can happen just sitting there. Happened to me while parked on Sunday afternoon (no clunk or similar sounds), got in the car and immediately saw all the warnings Flasher had and the car wouldn't go into drive. Tesla service was awesome and the car got flatbedded to Tampa. Received news this afternoon that they replaced the main battery pack and dealt with some other bits, the car is being delivered back to me tomorrow morning.

Wow, when it rains it pours. We have had a surge in early VIN pack failures reported here in the past few weeks. I'd be interested to learn the technical details/causes of all these failures.

Meanwhile, my A pack is happily humming along, supercharging as slow as ever, and suffering from a somewhat concerning amount of degradation. Ugh. On the bright side, everything else seems to be working great.