Good deal. I'm still relatively new to the e53 chassis having only had one for about a year and a half now in one form or another. Still learning. Unfortunately, I don't know answer to the two specific questions you have... so I am just trying to think of a way of testing that the system is functional.

By the description above it sounds like you could manipulate the rear level sensor to engage the headlight LWR. This would simulate very quickly going from an unweighted rear hatch/low fuel level condition to a heavily loaded/full tank condition to trigger the leveling. No?

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