VW Service "unable" to test battery capacity

[shawner123]

Any tips for getting VW service to understand what it means to test if the high voltage battery has more or less than 70% of it's original capacity?

I went to VW Downtown Los Angeles, and they told me there is no such test, they just suggested the regular service they do which includes "visual inspections" and when I asked if I would be able to see what the actual remaining full capacity of the high voltage battery was, in terms of the battery warranty, they said no.

They then reminded me that the range is all based on how you drive the car, which I have had for almost 7 years so I fully understand.

Great car, awful company. I've got a 2015 w/ 35k miles on it, and just figured i'd have them test it before the 8 year warranty is up, but they have no idea what I'm talking about.

Anyway, just venting. What a miserable company, never again! But the e-golf sure has been a great and fun car.

 

[f1geek]

Probably time to find a dealer who understands gross capacity and net capacity.

You can perform the test yourself. Charge the car to 100% SoC and then go drive it until you get the pack SoC into the red zone (less than ~15% SoC). Lower SoC will give a more accurate number, but be sure you are near a charging station. Record the final SoC, miles driven, and average efficiency since you began driving this trip. Using the data you gathered, you can calculate the usable pack capacity. Compare this to the 70% net capacity that triggers a warranty claim.

 

[shawner123]

Yeah unfortunately none in Southern CA seem to have a clue about the e-golf which is bizarre since for a while it was only sold here. Santa Monica can't do it, Van Nuys actually told me I needed to have my oil changed since the old 2015 head unit still has the scheduled message telling me to change my oil soon, it's really pathetic. Now DTLA is off the list, only one left to try.

Thanks for the info on calculating it myself, unfortunately I can't go to VW to try and start a warranty claim based on my own calculations, I would need the actual data back from VW's test so I really need that exact printout.

Honestly VW should just know about their own cars, especially when they've been on the market for 7 years, very sad.

Thanks again!

 

[f1geek]

I agree if your pack net capacity is below 70% then a dealer assessment is required to get warranty service. Maybe you need to contact VW USA to find a dealer competent in e-Golf service. You could always look outside LA if necessary. Maybe San Diego is a better choice?

 

[shawner123]

I wish! Except driving the e-golf would require stopping three times to L2 charge for 4 hours each time to make the 125 mile trip. So it would take me 28 hours of round trip traveling to drive to San Diego only to have the dealership then tell me they don't know what I'm talking about.

I think never buying another Volkswagen again is a better choice, but I sure have loved this car, a shame VW doesn't love it the same.

Unfortunately as we have all read in this forum, there are no VW dealers competent in e-golfs.

 

[f1geek]

Without DCFC it is a painful trip. I am used to making ~200 mile trips pretty easily. Yes, there are many accounts of dealer troubles, but there are also dealers mentioned here who have replaced battery packs, modules, charge ports, etc.

If you perform the capacity test yourself and determine the pack has not degraded enough to trigger a warranty replacement, then it is a non-issue. Otherwise, maybe contact Plug in America for help?

 

[shawner123]

Well Glendale VW actually knew what I was walking about! Unfortunately they told me it is a $400 test that I would be responsible for the cost if it passes, so I declined for now.

They did talk about a battery control system that should be reset every service that adjust how the car charges, which I'm sure has never been done, so they're going to do that, but the way things have gone w/ VW they're probably just charging me $150 for nothing.

Good times! Thanks again for the responses and letting me complain.

 

[f1geek]

Glad you found a competent dealer, though a “BMS reset” sounds like BS to me (a skeptic about many things). I charge my car to 100% SoC about once a quarter and I consider that a BMS reset since the cells get top balanced.

 

[shawner123]

lol that is exactly what I said, dammit I guess they got me, at least I got my wiper nozzles cleaned for $130. If you don't mind explaining, how would I do the math once I have my miles used and avg m/kwh

Thanks again

 

[f1geek]

To get the most accurate value it helps to have an OBDIi dongle (costs around $30) and software like Car Scanner to read digital SoC of the pack. You can also use the analog charge gauge to eyeball SoC, but your calculation won’t be as reliable.

Charge to 100%. Reset trip stats. Go drive until charge needle is in red zone (go as low as you dare).

Here is an example calculation how to use the data:

I drove 66 miles with an efficiency of 3.5mi/kWh for the trip and used 90% of the battery energy. So, the usable capacity based on this data point is 66mi/3.5mi/kWh/0.90= 20.95 kWh. Considering significant figures, 21 kWh is more precise.

Temperature will affect pack usable capacity. It is also best to repeat the test over time to observe any trends and to average out errors in data due to accuracy limits on SoC and efficiency.

Assuming 89% usable capacity of the 24.2 kWh pack (21.5 kWh), then 21/21.5=98% usable or net capacity. Your car will be lower.

70% of 21.5 kWh is 15.1 kWh, the warranty trigger.

 

[shawner123]

I'll give it a try thank you very much for taking the time to explain it. Have a nice weekend!

 

[kestutis]

Wow, just put a lease on 2019 egolf. Did visit a dealer for car and battery state. Can confirm that my dealer can't check battery's health as well. Basically what they said is that "you could, by charge-recharge and driving those km". But when I asked what is the battery warranty for and when it is considered replaceable, they just waved their shoulders. Turn's out it's the same all over. It's so sad, cause Zoe / Leaf have some great tools for that..

I'm from Vilnius, Lithuania.

 

[f1geek]

Yes, a bit sad most dealers are incompetent when it comes to EVs. That will change over time.