For the 2 years I've owned the car its had a persistent 90mA battery drain when everything is shut off. I tried to find it a few times with no luck. If the cars sits without being used for a week it starts up fine but the closer it gets to 2 weeks the more likely it is that it won't start. The simple solution has been to hook it up to the charger in the garage if its been sitting for a few days but the rest of the family doesn't seem to care for this car's special needs.
2 dead batteries later I gave it another shot. Hooked up the amp meter in line with the battery and methodically pulled every fuse I could find 1 by 1. That's all 3 fuse boxes plus the fuses on the K40 relay. I also isolated the alternator, pulled the stereo and unplugged the ECU and TCU and checked the trunk light. No luck, its always pulling 90mA. According to MBcluster it should be pulling 20mA or less with a couple of months worth of reserve between starts.
https://youtu.be/yAf9I12XAzg
I have isolated the drain to the large gauge wire going forward from the battery, not the multitude of orange wires going to the rear fuse box. I also isolated the + terminal on the inner fender with no luck.
This isnt a huge issue but its getting annoying now that we're putting most miles on the other cars. I appreciate any fresh ideals or potential problem spots on the w210 I might have missed.
Thank you