Hi,
I didn't gave the solution yet cause I wanted to be complete and sure that it works definetely.
So yes you're right, it's effectively the eNBT from BimmerRetrofit. My battery lasted 2-3 days before totally discharged each time because my car made a permanent loop in alternating sleeping and wake-up mode. The permanent discharge measured was 170 mA.
(Bimmer said the discharge of my battery in deep sleeping mode was normal at 200 mA (0.20A !) with their eNBT adapter pluged, whereas BMW said normal discharge in TIS is 10 to 20 mA (0.01 to 0.02A) for my model so when I said that the problem was their eNBT they went furious and said :
"Please do your math, if you not very familiar with electronics and electronic math please ask someone to help you."
"Also read more about BM vehicles and specifically about how much current they normally drain when sleeping."
So I needed to find the right solution without any help and after very long time searching i found it :
So it was compulsory for me to bring power since a source +12v after ignition into the eNBT. That was the only solution not to drain the battery. Now the car goes deeply into sleep with no more problems anymore of battery discharge. Now, the consumption of current is 0.01A to 0.02A.
The only inconvenient is that the system is totally operationnal after about 20 seconds whereas it is immediate when we have a good eNBT device.
So the eNBT from BimmerRetrofit is a well piece of s.it ! (and the company obviously too, because they was totally unable to give me the solution I found above. They just took me for a newbie whereas I installed entirely the NBT kit into my 5 serie E60 and all works so perfectly and they do the same for every customer asking something to them). Absolutly everything has a price in this company, all is very expensive. The devices sold have very poor finition and electronic is not terminated (prevent the car going into sleeping mode). Very bad behaviour and customer experience !
I never buy something again in this company.
Now for me it's definetely resolved so we can qualify this thread "Resolved" unless someone give me a better solution...