Velvetronic servomotor nightmare FIXED! (002DD6, 002DE3)

[PM48]

BMW X6 35i 2012 with 37k. N55 engine.

The Velvetronic servomotor (VSM) started to make clicking/retelling sound when closing or opening driver door. It continued for several months until it completely died. I did enough reading to find out that it needs to be replaced. There are several YouTube videos on how to do it. I decided to do it myself as it is a strait forward process. It went smooth with only one issue I was unable to get ISTA+ working to perform “Velvetronic servomotor start-up” which is a must. I took it to the local shop that worked with European cars to have it done. Car ran fine for several months.

One day I went to the mountain to hike when outside temperature got close to 100 and on my way over I had water pump frailer. Needless to say I had to stop multiple times to open my hood and have the engine to cool down so I could make it home. I got home, read the codes that confirmed the failure. Ordered new parts and replaced water pump along with thermostat. (there are many YouTube videos on how to do that as well). Car ran fine after for couple of weeks and than again: “engine mulfunction reduced power”. Read the codes 002DD6 - Velvetronic servomotor, position sensors, short circuit or line disconnection and 002DE3 - Velvetronic servomotor, activation, volt phase, line disconnection.

I decided to take it to the BMW dealership this time for diagnostics as I could not believe that basically brand new Velvetronic servomotor failed again. The dealership made a verdict that Velvetronic servomotor and eccentric shaft are in need of replacement for 6K. Well, I did it once so I could do it again plus the eccentric shaft replacement did not seem to be too intimidating according to the several YouTube videos. Ordered new parts, opened the engine up, removed eccentric shaft and did close examination for wear. I was unable to find any wear or damage on it. Took it to the local car repair shop to see if I am missing something and was told that it looks brand new with no wear even on bearings. (Well it has 37k only with very mild driving habits of mine).
I decided to replace the bearings on the shaft anyway just because I already had the parts and they are not that expensive vs eccentric shaft itself that runs about 1k new and I returned.
I put everything back together, got good version of ISTA+ with VSGIAG adaptor, read the codes and got the same codes 002DD6, 002DE3. Tried to run “Velvetronic servomotor start-up” with ISTA+ with no luck. I got hold of the service man that took care of me at the BMW place and expressed my frustration with their diagnostics just to be told back that I ether bought bad parts (since I did not buy them from them) or I did not put things back together in the right way.
I replaced ISM (Z11) as it contains relay and fuse for VSM, had software update done at dealership but it didn’t fix anything.
I finally had a brain storm and decided to use voltmeter to take some readings of VSM
I connected volt meter negative to the engine block and used positive to check for voltage on the plug on harness that attaches to the VSM (with engine running). The leads are numbered and that is what I got. #1 empty (no pin) #2, 3, 4, 8, 9 I got 4.6V. #10 5.4MV, #11 5V, #5 12.1V, #6 12.19V, #7 3.9V.
Pins #5, 6 and 7 supply 12v dc to the VSM as it is brushless and calls for 3 positive leads with no ground needed (you can read up on brushless motors). So, something was off with #7, 3.9v instead of 12v. I got the same readings directly from computer as I unplugged harness from it. Well that means I got my ecu going bad, probably it got damaged when water pump failed.
Bought used ecu from ebay, had it cloned. Put everything back together, ran “Velvetronic servomotor start-up” and 1k later still running strong.

I hope this can help someone.