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BSM: V_ess too low during precharge, t2

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So, I went out to McDonald's to get myself a well-deserved McFlurry, I'm driving home, was 1/4 mile from my house (if that), drove over a speed bump (that I've driven over 200+ times before), heard a very-ominous "pop" sound from the battery pack area, and the whole car just shut down.

I have a fault light on the dash, it won't go into anything but Park or Tow Mode (thank God). Can't even select Neutral. Was able to grab a neighbor and we pushed it into my driveway.

I called Tesla Roadside assistance and they're sending a tow truck out tonight to pick it up.

The little display screen (VDS? VDM?) shows "BSM: V-ess too low during precharge, t2". I tried to Google that and that phrase comes up on literally ONE website (the OVMS site with a list of all the possible error messages) so that's no help.

I tried pulling the little fuse under the hood, made no difference. I know where the big orange disconnect is in the battery compartment but, I can't even get my hand in there to touch it, let alone get a grip on it enough to pull it. And, if I did, I'd never get it back in. Is there some trick to that (other than driving around with an 8-year-old with teenie-tiny little hands to reach in there and grab it)?

But, I don't think it matters; it didn't seem like a software fault. I think I broke something (the "pop" sound kinda gave that away).

FML
 
I can't even get my hand in there to touch it, let alone get a grip on it enough to pull it. And, if I did, I'd never get it back in. Is there some trick to that (other than driving around with an 8-year-old with teenie-tiny little hands to reach in there and grab it)?

Proper way it to remove Tire, and then wheel liner to get to the ESS Service disconnect. In a pinch I've use an car antenna and bend the end of it in a tiny U like hook, make sure to lift the plastic handle out 90 degrees and then use little hook to pull it out. Note be careful in pulling our the ESS disconnect, and pull it out straight out as that plastic handle is easily cracked, as I broke one already.

Oh also if you able too, disconnect the 12v battery, does the car power off instantly?
 
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NO!!! Bought it used, as is, about 3 months ago.

I hate to say this but it sounds like a fuse blew inside the ESS which means it needs to be dropped, investigated, and the fuse replace as well as what initially caused the fuse to blow.

From spaceballs in the following thread:
Pics/Info: Inside the battery pack - Page 15

"Roadster ESS sheet fuse is this http://www.discountfuse.com/v/vspfil.../PDF/a50qs.pdf it’s slow blow type, i.e. takes ~1,800amps to blow this 400amp rated fuse in 1 second."
 
I hate to say this but it sounds like a fuse blew inside the ESS which means it needs to be dropped, investigated, and the fuse replace as well as what initially caused the fuse to blow.

From spaceballs in the following thread:
Pics/Info: Inside the battery pack - Page 15

"Roadster ESS sheet fuse is this http://www.discountfuse.com/v/vspfil.../PDF/a50qs.pdf it’s slow blow type, i.e. takes ~1,800amps to blow this 400amp rated fuse in 1 second."

I'd second that. I've been in the drivers seat when that happens, and the pop sound followed by everything going dead (except for brake lights, hazard lights - all the emergency stuff) sounds exactly like what happened to me. Of course, I was about to drive away from the Tesla service centre at the time (with a couple of Tesla engineers looking on), so my location was a lot more convenient than yours.

Good luck, and please let us know what they find.
 
But I'm sure you didn't hear a pop which is an indication of the fuse blowing. Good to know about the error code, we should document it on the wiki.

Maybe it was a relay he heard. I am not sure if I could hear the difference.
But I was able to get my car to drive again by cycling the key.

@habious
You get the debug messages, so you seem to have access to the service menu?
You could check the values for V_bat... There are two different sensors and values for it. You find one in the ESS menu and the other in the PEM menu.
 
Maybe it was a relay he heard. I am not sure if I could hear the difference.
But I was able to get my car to drive again by cycling the key.

Nope. Cycling the key made no difference. The fault light stayed on. Even after I got it into the driveway, shut it down, and left it for several hours (12V had shut down). It would wake up and unlock when I hit the unlock button on the fob but, same problem when I put the key in and turned in. Got the error message on the VDS, and the car wouldn't come out of park.

@habious
You get the debug messages, so you seem to have access to the service menu?
You could check the values for V_bat... There are two different sensors and values for it. You find one in the ESS menu and the other in the PEM menu.

I don't have access to the service menu. This is just what came up on the center touch screen. I have an OVMS but, I haven't had the chance to install and configure it yet (it's been ridiculously cold here the past month).

Tesla towed the car away last night. They called today to tell me that they're looking at it but, they had to send the logs to the mothership out in California, and probably wouldn't have an answer back to me on what's wrong (and what it's gonna cost!!!!) until at least tomorrow.

2015-01-12 17.02.00.jpg
 
1/19/15 Update:

Rockville Service Center finally sorted out the problem with my Roadster. They didn't have specifics but, there's an internal issue with the battery back. They're going to have to pull the pack and ship it back to CA for repair/refurbishment. It's going to be about a 2 week turnaround.

Repair cost - ~$4,500.00

2 weeks is better than 2 months...and forty-five hundred is better than forty-five thousand but, considering I've had the car 3 months, and put a whopping 2K miles on it, I'm a little less-than-thrilled with the reliability.

For what I spent on the car, I could have gotten into a used Ferrari. I intentionally steered clear of that because of the high maintenance cost and potential repair costs. Oops.
 
1/19/15 Update:

2 weeks is better than 2 months...and forty-five hundred is better than forty-five thousand but, considering I've had the car 3 months, and put a whopping 2K miles on it, I'm a little less-than-thrilled with the reliability.

For what I spent on the car, I could have gotten into a used Ferrari. I intentionally steered clear of that because of the high maintenance cost and potential repair costs. Oops.

Hate to say it, but when you buy a car used you're buying "as is" and a previous owner has a variable into how well or dependable the car will be. You're in the same boat with any car. There're many owners of Roadster's who only have only had to do the annual maintenance, and also some who have done costly repairs. If you're worried about cost of repair then a CPO would have been your best route or to wait for an owner who put up a Roadster that has the extended service plan. One thing about buying a low mileage Roadster or low mile anything, its nice having low miles, however when more miles are on a car the whole system has been tested and any part that's on the verge of failing would have failed. Any exotic car has its share of risks, and the Roadster was on the verge of a Prototype marketed and sold to regular customers. You have to understand what this car really is and where it came from before you put money down on it. Electric cars also have not had as much run time as the ICE vehicle to keep improving upon them such is components and such. I think they're very reliable myself hence why I have an electric car, motorcycle, skateboard, and bicycle. ICE cars have had over a century to get it right and they still can't get it right. Look at the cars in the 70's/80's, junk.
 
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Hate to say it, but when you buy a car used you're buying "as is" and a previous owner has a variable into how well or dependable the car will be. You're in the same boat with any car.

All true. Just venting a bit here, more than anything. I have no plans to sell the Roadster anytime soon (once I get the darn thing back, that is).

Any exotic car has its share of risks, and the Roadster was on the verge of a Prototype marketed and sold to regular customers. You have to understand what this car really is and where it came from before you put money down on it. Electric cars also have not had as much run time as the ICE vehicle to keep improving upon them such is components and such. I think they're very reliable myself hence why I have an electric car, motorcycle, skateboard, and bicycle. ICE cars have had over a century to get it right and they still can't get it right. Look at the cars in the 70's/80's, junk.

Also true. I did, however, do quite a bit of research before I plunked down the cash for this. I also had a Pre-Purchase Inspection (PPI) done by the nearby Tesla Service Center before I bought it. I get that "stuff" happens and that no car is going to be 100% reliable. And I knew going in that this was a used car, as-is, no warranty. I rolled the dice (and lost).

Did they say how long is the warranty going to be on the repaired pack?

No, they didn't. Very good question. I'll call tomorrow and ask.
 
Wanted to give a final follow-up to this thread, for future reference.

They sent the battery pack back to the factory to be refurbished. Once they got the pack back and reinstalled it, they discovered an additional problem with the PEM - it wouldn't take the flash upgrade they were trying to do. So, they ended up replacing the PEM also.

The good news is that, since they'd already quoted me a price for the repair, they replaced the PEM under goodwill.

As for the warranty, both the refurbished battery pack and the replacement PEM have a one-year (from date of installation) unlimited-mileage warranty.

I have the car back and it seems to run just as before. I've seen a (slight) increase in Ideal Miles from a normal (220V/40A) charge. 181, up from about 174. I haven't had the need to do a range charge with the car yet, nor have I run the pack down below half (I rarely do anyways).

...and I got a couple of cool red Tesla scarves to go with the repair!
 
Glad you got the car back and on the road so quickly!

I think that Tesla has treated you very fairly...a new PEM is very expensive...pretty sure only the battery costs more to replace.

Wanted to give a final follow-up to this thread, for future reference.

They sent the battery pack back to the factory to be refurbished. Once they got the pack back and reinstalled it, they discovered an additional problem with the PEM - it wouldn't take the flash upgrade they were trying to do. So, they ended up replacing the PEM also.

The good news is that, since they'd already quoted me a price for the repair, they replaced the PEM under goodwill.

As for the warranty, both the refurbished battery pack and the replacement PEM have a one-year (from date of installation) unlimited-mileage warranty.

I have the car back and it seems to run just as before. I've seen a (slight) increase in Ideal Miles from a normal (220V/40A) charge. 181, up from about 174. I haven't had the need to do a range charge with the car yet, nor have I run the pack down below half (I rarely do anyways).

...and I got a couple of cool red Tesla scarves to go with the repair!
 
This looks similar to Habious' error above. No pop, but last night I got a BSM: V_ess too low at end of precharge. ID:276
It happened right when I plugged it into the HPWC after a 30 mile easy drive at about 85F ambient temp. Nothing was particularly hot. I have my current set to 40A max. I cleared the error, restarted the charge and the charger threw an error and the red service light came on. I unplugged the charger, shut the charge port door, reset the breaker, and plugged in again. No problem. Later I went to back my car out to wash it and the error came up again. I couldn't move the car. I tried a few key off/ons and a few charge port door resets and the error went away. It was a scary few minutes, though.

I did drive the car very hard this weekend. I range charged it and drove 90 miles round trip to the track on Sat for driving school. Returned with 31% charge. I did the same on Sunday, but for an Autocross event. Returned with 50% charge. The only other weird thing I did was get new tires yesterday morning, but the shop used only a floor jack at the right points. All TPMS are functioning.

After washing my car, I pulled it back in, and hooked it up to the charger with no issues. No issues on my drive this morning. I'm hoping it was a fluke. Any ideas why this would happen? Would there be something in the logs that might give more info?