fuel gauge wont work

There is a service bulletin out on those gauges. Look at this YouTube video and try a reset....of pulling the fuse and then place back in https://www.youtube.com/watch?v=Jkuap-JM7To

There are 2 sensors in the tank for fuel levels, one that takes care of full to half and the other does half to empty...I was told because the tank is 95 liters, it requires 2 sensors

Ahhhhh found a good possibility. Under the back of passenger seat is an electrical set-up which will cause havoc if you get it wet.(I have 2006 350ml) It is easily disturbed by slightest spills, coffee(ahem which I did), sodas, water etc. Anyway, my locks, lights etc. started to go haywire & it became worse the next day. I googled my problem & read about others who had similar problems & they said it was because of a spill in car. I a) moved the carpet then plastic covering from under the back of passenger seat, b)turned my car heater on FullBlast to blow on rear floor area. Yes I used the heater therapy for quite awhile. It fixed the problem!!! No expensive electrical repairs needed from the Benz Dealership needed. I repeated an accidental slight spill again, I thought it was small enough to not cause a problem...but a few hours later my door locks began to do their own dance, so I immediately repeated the steps to dry out the electrical system under the passenger seat. Thought to ponder: Be careful if you have the carpet shampooed because if you or the detail-shop gets this area too wet...Yes a problem may be at hand.

one last thought. There's a common fault in the system, but an even larger problem is that there is no manual override. No handle, no way to pull the hatch down and overcome the closer mechanicals. Just a terrible design. It could be a rear SAM. It is some burned computer located in the back under the passenger side taillight.. installed new from the MB dealer parts store and no programming is necessary

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