start at battery , then start with sams , 10gauge leads,etc , recently I found it was a cluster on a w 211fuse 64, start with basics fuses first , your going to need wiring diagrams

Test the same way you did before.

OK, Thanks! (Sorry, I'm a little lost when t'shooting electrical/electronics)

Sincerely -

you can do the voltage drop test without doing the battery isolation. Once you find the faulty circuit, you can do the battery disconnect/jumper lead test to verify your results.

Correct battery voltage of 12.6V is mandatory for the loss test. close doors etc as mentioned above so the car actually goes to sleep.

__________________
2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)