Sudden range nose-dive: Advice?

[CruzInVA]

Hey Gang,

My 2011 2.5 Sport Held steady for years at around 185 to 190 miles on a Standard charge.

Suddenly a month or two back, I noticed a sudden drop to around 165, and it has been creeping downward ever since.

Now it is sitting at an estimated 148 Ideal range off a Standard charge.

I expect the range to creep down over time, but this seemed pretty dramatic after being so steady for so long.

Car has 31000 miles on it.

I’ve always tried to be very careful with my charging. I’ve only ever charged for Range once. I use the auto start timer to minimize the time it will sit fully charged before I drive it. I use Storage mode when I know it is going to sit for more than a couple of days.

Is there anything I can do, or am I just losing panels and that’s it for ever getting the range back up short of a compete replacement or upgrade?

Any advice that a non-techie owner might try?

Thanks!
Ted
2.5 Sport #1422

 

[spaceballs]

Pull logs on USB thumb drive open with excel, or enter service menu, look at ESS/SOC menu see brick Min/Max/Ave. Guessing you have a brick that is getting weak.

 

[markwj]

I second spaceballs' advise. Pull the logs and check the brick min/ave/max. If that is more than about 3% then you probably have a brick going/gone bad. There is also a file in those logs that lists the voltages of each brick, to see if it is just one or more.

You can try a standard mode charge to as full as it will get, then leave it there plugged so it can balance. The DIAG screen can show you the balancing process. If you see all 1's with just one or two 0's, then that also shows the issue.

 

[CruzInVA]

Thanks guys!

So how do I access the service menu and DIAG screens?

 

[backmost]

I'll PM you

 

[markwj]

If you have OVMS, these are remotely reported as metrics v.b.c.level.min, v.b.c.level.avg, and v.b.c.level.max. Summarised in v.b.health. We also calculate an overall v.b.soh to give a simple percentage indication of overall battery health (which takes these, as well as CAC, into consideration).

I suspect that we are going to see a lot more of these in the coming few years, and it is good to keep an eye on these metrics (although not much you can do other than replace the sheet/battery if a brick fails).

 

[thefortunes]

If you have OVMS, these are remotely reported as metrics v.b.c.level.min, v.b.c.level.avg, and v.b.c.level.max. Summarised in v.b.health. We also calculate an overall v.b.soh to give a simple percentage indication of overall battery health (which takes these, as well as CAC, into consideration).

I suspect that we are going to see a lot more of these in the coming few years, and it is good to keep an eye on these metrics (although not much you can do other than replace the sheet/battery if a brick fails).

Where are these reported @markwj ?

 

[bolosky]

I use the auto start timer to minimize the time it will sit fully charged before I drive it.

This might lead to your battery being unbalanced, because the time after it charges is when balancing happens. When you look in the logs (or in the service screen), see if there's a large difference between max and average amp hours per brick. If it's large, then you might need to let the car sit fully charged for a number of days to rebalance (range charge is better, but with an original battery standard charge works, too).

 

[PowerSource]

Use the 110 plug and let it balance itself out. Typically you get higher rated ideal miles after using 110 vs the UMC

 

[ML Auto]

I hate to say it but you are going to need a new battery or at least a replacement sheet if Tesla will still do that. A few months is not nearly long enough to get the pack that far out of balance and show that much range loss. The range is based on the lowest brick voltage. Check ESS voltages in the service menu and you will find your lowest (bad) brick. The max and min voltages should be only around .03V apart.

 

[markwj]

Where are these reported @markwj ?

Simplest is:
metric list v.b

 

[CruzInVA]

Thanks for all the info and tips, guys! I knew I could count on you all.

Here is what it looked like this morning after charging it back up on Standard using my 30/240 Clipper Creek Wall charge yesterday evening, then leaving on the 110 overnight for balancing.


I will keep trying, and try to find a time I can leave it for several days on the 110 to see if I get any improvement.

 

[SSonnentag]

Could it be a bad (internally-shorted) 12V battery?

 

[spaceballs]

... Here is what it looked like this morning after charging it back up on Standard ...

Min of 75% and Max of 88%, yeah you need to pull your logs and see which ones are have the lowest voltage, highest voltage at the end of a charge And near empty.

 

[markwj]

Vave 4.07V, Vmin 3.97V (#4), and Vmax 4.08V (#27) does not look good. It seems that you have a bad brick (#4), and the average being close to max would support that guess. You've got a bunch of bricks up at (and close to) 4.08V, and one brick down at 3.97V. Your SOC min 75% and max 88% reflect that. You can't drive it lower than the SOC LIM, or charge it higher than the SOC MAX.

Full logs would provide more clarity, but I predict this will get worse every time you cycle the battery (drive, charge). You'll see Vmin and SOC LIM fall each time, and the spread get wider. Likely the only solution is to replace the bad sheet, or battery. Sorry to say it, but the car needs to go in to Tesla for a look, and that will not be a quick solution.

 

[ML Auto]

Bad brick #4 confirmed. Balancing stops at 79% SOC MIN so unless you externally change the brick, you have limited time until the car is completely dead. You might be able to range charge it to get #4 over 79% and get it to balance. If you can do that you can change it every day to buy you some time, but you should get ready for a pricey repair.

 

[ICON]

Yep, been there....once one brick goes it's a downward slope you'll loose 10% a week ...order the R80 if you intend to keep the car!

 

[CruzInVA]

Hey gang,

Sorry to have been out of the loop for a while, but life does have away of interceding at times.

An update: I took PowerSource’s advice and tried leaving for extended periods on the 110 charger to see if that would help improve the balancing. Turns out, it helped! Still not back up where we would like it, and #4 is still clearly the weak brick, but the numbers do seem to be improving a bit.

Here are the screen shots from yesterday morning. What do you guys think?

 

[spaceballs]

... What do you guys think?

Keep an eye on SOC Min/Max, see if over time if it gets worse/same/better.

 

[CruzInVA]

On July 17, it was showing SOC MIN 75%, MAX 88%

On July 30, SOC MIN 82%, MAX 88%

This morning, August 1, I noticed that the Ideal Range was back above 170 for the first time since I don’t know when.

I didn’t check the logs this morning, but things do seem to be getting better.

I’ll leave it on the 110 again for a couple of days and check in again.

I noticed another whole thread dedicated to the debate over the pros and cons of the 110 V charger for Roadster battery life. It seems to be a somewhat controversial topic, but for what it’s worth, it certainly seems to be doing some good for my car.