Had an interesting finding after my first service appointment earlier this week and wanted to share for those of you who live in the northeast and use the EZ Pass toll system.

Added disclaimer: not sure if this affects the pre-facelifted W211s.

I had a complaint that my left front parktronic sensor would be on full both visually and audibly whenever I start the car, am in reverse or hit the brakes coming to a full stop. Thought I'd had a faulty sensor...think again!

They diagnosed the problem to my external EZ Pass tag mounted on the front plate and after removing it, they said the problem was rectified. Not being a believer, I then reinstalled the tag to the lower portion of the front plate - and sure enough, the problem returned. And yes, it again went away when I removed the tag...

So, I'm left to using the internal windshield mounted tag only to avoid triggering the parktronic system - but at least I can be safe in the knowledge that the system is sensitive to within 2" of the center of the front bumper.