[kardkovacsi]

Hi,

I would like to share this story, hopefully helps for the other 330e owners as well. First of all BMW provides 6 years/100k kilometers warranty for the high voltage battery. My car (I'm the first owner) 5 years old and has only 66K in the odometer.

Two months ago it started dropping the Max eDrive mode from 20%, after a while it dropped 30% and usually and error code was shown in the iDrive system that the battery needs to be cooled down however the outside temperature was normal, around 20 degrees celsius.

I have downloaded an ISTA+ to check the high voltage battery capacity. It was around 80% but there were no high voltage battery related fault codes. As it getting worse and worse I called the dealership where I bought the car. They advised a general diagnostics because they thought one of the five battery modules has a short circuit. So they checked the car but they found nothing. That was really weird as the car dropped the Max eDrive mode around 50% of the battery and there were other strange things like stop the car with 40% in the battery and starting it after a few hours and it shown 3%.

Once the problem occurred again, I checked the car with ISTA and bingo, and the error was: Voltage of battery cell, maximum difference above the threshold value. I talked with BMW technician whom specialty the electronics (fortunately he is really an enthusiast of his job) that this fault is a virtual fault code, calculated by the ISTA+. When I checked the car the battery was empty, but when the BMW service checked the car the battery was almost full as I arrived there with 70% in the battery. If the battery is full, the cell levels are OK, which explains why the problems occurred only at low battery level, because the car appropriate module identified the problem and simply throttle down the high voltage system.

I went back to the BMW service with an empty battery, they checked it again and confirmed that one of my battery modules needs to be replaced under warranty.

A few stats. I had 3800 total charges which is identical to 2800 full charge and have made 45K electric only kilometers from the 66K.

[Ntrigued]

What were the symptoms of the car for the state of your battery? Did the car not use edrive after a certain percentage of charge? Did it seem like the edrive was noticeably weak after a certain battery percentage? Did you replace your auxiliary battery?

I have been noticing very similar issues with my 330e and my max edrive is not available from even 80% charged battery. My range has dropped significantly and I'm lucky if I get 10 miles of pure electric drive now. I replaced my auxiliary battery and that solved several faults, but I am still experiencing issues after a certain battery percentage like max edrive not available -system request, and it will say edrive not available due to heating/cooling of high voltage battery.

[kardkovacsi]

Originally Posted by Ntrigued

What were the symptoms of the car for the state of your battery? Did the car not use edrive after a certain percentage of charge? Did it seem like the edrive was noticeably weak after a certain battery percentage? Did you replace your auxiliary battery?

I have been noticing very similar issues with my 330e and my max edrive is not available from even 80% charged battery. My range has dropped significantly and I'm lucky if I get 10 miles of pure electric drive now. I replaced my auxiliary battery and that solved several faults, but I am still experiencing issues after a certain battery percentage like max edrive not available -system request, and it will say edrive not available due to heating/cooling of high voltage battery.

Yep, as I said it started dropping from 20% but now it's between 60-80%. Yes, it is noticeably weaker the previously. I have not changed the aux. battery, I saw in the ISTA that there is a fault code the aux battery is aged.
This is the exact error message in the iDrive what I get as well, the system request.

I can drive only 8-10 kilometers (5-6 miles) on pure electric mode and then the engine kicks on. The car shows around 40% in the battery but it is not real. If I park the car with such battery level, after 3-4 hours it will show 2-3%. If you have ISTA+ I recommend to check the car when the battery is empty (it is very important as the problems do no come around when the battery is full)

The BMW battery setup is far from ideal. There are 5 modules each have 1x cells (do not know the exact number) and the whole pack is in series (I hope I use the right word for it as I'm not a native English speaker, I mean series circuit). The max available battery capacity is adjusted to the weakest module. My current battery capacities are 80, 79, 81, 71, 80. Yes, the 71 is the problematic module in my case. A month ago it was 78% but I assume it does not have 71% just the car adapts slowly.
If you have ISTA+ you can check the battery module levels. You have to start ISTA+, connect, etc. There are some battery related functions under the Body/hybrid car. Read for example the battery statistics etc. It will show the max capacity but unfortunately it does not show the exact module capacities in the UI but it logs to the FASTA log files. Quit from the ISTA. Open the EC-APPS\ISTA\FastaOut folder, there should be behdat files. Rename it to XML extension and then open it in a browser. It is a standard XML file. Look for the STAT_MIN_KAPA_MOD entries, it shows your battery module capacities.

[Alpine530e]

A few stats. I had 3800 total charges which is identical to 2800 full charge and have made 45K electric only kilometers from the 66K.[/QUOTE]

Where did you find the electric only km's? I was able to see charge counts and last 4 charge sessions but it never displayed the km's of electric only use. Is that in the XML info?

[kardkovacsi]

Finally it ended up that BMW replaced (under warranty) the remaining 4 modules as all of them had errors according to the ISTA+.

It was quite "interesting" as I got a lot of drive train issues before they changed the battery. Like overvoltage, undervoltage, charging electronics overvoltage at DC connection.

It's worth mentioning that they increased the price of a battery module. Now it costs around 1000 euro + VAT per module from around 550 euros. It would cost around 7500 euros including labor and VAT if I had to pay for that. The older modules with less capacity (1.55 kWh) is more expensive now than the newer ones (2.0 kWh) which is quite odd.