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Please Help - 2014 MS Battery Replacement

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Correct me if I'm wrong, but I don't think actual 70kwh battery could be paired to a car by Tesla and display "P85" without some non-standard changes on the MCU side. I'd expect the pack label is incorrect, but would be worth a CAN dump to verify.

I've tried this as a potential cost-saving solution for P85 owners who just want to be able to get driving again, and this works fine for non-performance cars. But the SPORT type drive unit cars (RWD or AWD) won't run on 14-module packs.... with the notable exception of the newer 14-module 90 packs where Tesla cheats and bumps max output current in the drive unit firmware to account for the lost power from the lower voltage of these packs (which I think is shady, since it increases wear on electronics 12%, but it's not the biggest issue I've ever seen with Tesla).
Good point on the "P85" display. My understanding based on a few other posts within TMC (don't have time to find them now) is that changing the display is a separate step by the technician. I some cases owners got a 90 but display still said the previous 85. Those owners had to go back to Tesla to make the 90 display.
 
  • As many of you have point out – a 70kWh battery will not provide 234 miles of range. A new S70 had a full range estimate of only 210 miles.
A point of correction, a new brand new S70 was rated at exactly 234 miles of range, not 210 (that's a 60).

The fact that your car showed 244 miles of range right after you got it back (as you indicated in your first post) - higher than a brand new 70kwh pack would show in the same car - is a strong indicator that Tesla's story passes muster and it's a remanufactured 85 in an old 70 shell.
 
Good point on the "P85" display. My understanding based on a few other posts within TMC (don't have time to find them now) is that changing the display is a separate step by the technician. I some cases owners got a 90 but display still said the previous 85. Those owners had to go back to Tesla to make the 90 display.
There's some instances where a "wrong pack" error won't be thrown (user facing, at least) despite the MCU's pack config being mismatched (in which case the display would be wrong)... but a 70 in a P85 would definitely throw a "wrong pack" error without some non-standard shenanigans. (Unless something with that's changed very recently.)
 
There's some instances where a "wrong pack" error won't be thrown (user facing, at least) despite the MCU's pack config being mismatched (in which case the display would be wrong)... but a 70 in a P85 would definitely throw a "wrong pack" error without some non-standard shenanigans. (Unless something with that's changed very recently.)

If OP had Scan My Tesla, or other similar app, they would be able to see which battery was installed, right?
 
@tjv85 - What's the latest?
Thanks for the follow up. I haven't done anything more here. It appears I got a weak 85kW battery. I don't understand why I had to buy new rails to get the same size battery to fit my car. It should have been a drop in.

Also, how many people missed 70kW label on the reman battery thru out the whole process. There had to be two or three people in the service center alone. I am not impressed.
 
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Thanks for the follow up. I haven't done anything more here. It appears I got a weak 85kW battery. I don't understand why I had to buy new rails to get the same size battery to fit my car. It should have been a drop in.

Also, how many people missed 70kW label on the reman battery thru out the whole process. There had to be two or three people in the service center alone. I am not impressed.
Just the luck of the draw with REMAN...

Based on your estimate pics in post #17, they didn't replace rails, just covers.
I replaced those myself on my car, they're plastic and damage easy...
 
Tesla is going to lose a lot of customers over battery replacements and associated issues in the coming years. People really think Tesla can continue to treat customers like this and expect them to buy anything from them in the future? They need to revisit what they are doing w the older cars asap. Toyota has built a brand on longevity and reliability. Tesla has built a brand on tech and performance. But if these cars cannot be held to be reliable and get replacement parts at a fair cost it won’t end well for Tesla. This won’t happen overnight but the damage service centers are doing to Tesla’s reputation right now is irreversible
 
Tesla is going to lose a lot of customers over battery replacements and associated issues in the coming years. People really think Tesla can continue to treat customers like this and expect them to buy anything from them in the future? They need to revisit what they are doing w the older cars asap. Toyota has built a brand on longevity and reliability. Tesla has built a brand on tech and performance. But if these cars cannot be held to be reliable and get replacement parts at a fair cost it won’t end well for Tesla. This won’t happen overnight but the damage service centers are doing to Tesla’s reputation right now is irreversible
Doubt it'll make a dent...
If u look at 2013/14 car numbers, its about 50k units produced/sold
All the failures reported here and facebook plus unspoken/silent ones, still probably only equals to like 1-2%...
That leaves 95%+ happy customers

Also, wk057 said that most HV battery issues got fixed in 2015 so failures should be even more rare.. We shall see..

Silver lining: a lot of 2013/14 cars had FUSC, so some money is already saved on those cars and w/ new battery u can continue using free electricity n save more.
 
Doubt it'll make a dent...
If u look at 2013/14 car numbers, its about 50k units produced/sold
All the failures reported here and facebook plus unspoken/silent ones, still probably only equals to like 1-2%...
That leaves 95%+ happy customers

Also, wk057 said that most HV battery issues got fixed in 2015 so failures should be even more rare.. We shall see..

Silver lining: a lot of 2013/14 cars had FUSC, so some money is already saved on those cars and w/ new battery u can continue using free electricity n save more.
You can bet I’ll be back to report on the status of my battery and how Tesla treats me. I’m the perfect sample w a late 15 where the issues were said to be solved.
 
You can bet I’ll be back to report on the status of my battery and how Tesla treats me. I’m the perfect sample w a late 15 where the issues were said to be solved.
What exactly do you expect them to do to retain your business?

Things fail. Batteries have finite lifetimes. Warranties exist for a reason, but when they’re done they’re done.
 
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You can bet I’ll be back to report on the status of my battery and how Tesla treats me. I’m the perfect sample w a late 15 where the issues were said to be solved.
I said it before and I will say it again. Don't trust Tesla. I have never heard of Tesla taking a 70kwh battery pack and increasing it to 85kwh by adding modules. Maybe someone can chime in and correct me, but I have never heard of it. If the sticker was placed there by mistake have the service center correct it, I would have a 3rd party check the kwh of the battery pack to be sure.
 
I said it before and I will say it again. Don't trust Tesla. I have never heard of Tesla taking a 70kwh battery pack and increasing it to 85kwh by adding modules. Maybe someone can chime in and correct me, but I have never heard of it. If the sticker was placed there by mistake have the service center correct it, I would have a 3rd party check the kwh of the battery pack to be sure.
Is it possible Tesla just reused the shell as some have suggested - 85 guts in a 70 housing? I am not sure what would have caused them to do this, but is it possible?
 
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I said it before and I will say it again. Don't trust Tesla. I have never heard of Tesla taking a 70kwh battery pack and increasing it to 85kwh by adding modules. Maybe someone can chime in and correct me, but I have never heard of it. If the sticker was placed there by mistake have the service center correct it, I would have a 3rd party check the kwh of the battery pack to be sure.
They don't add anything, they just re-used the shell and put 16 original modules from some other working 85kwh battery
Very easy to check voltage with SMT and you'll know if its 16 or 14 module pack.

Is it possible Tesla just reused the shell as some have suggested - 85 guts in a 70 housing? I am not sure what would have caused them to do this, but is it possible?
Yes.
Shell can get damaged easily during accidents or running over curbs/debris, while internals will be fine.
FYI, all S/X shells are the same size for 60/70/75/85/90/100 kWh packs with exception of Refresh/Plaids maybe, not fully sure about those...
Pre-2015 cars had different top covers and fuse location.
 
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