Denis_E55

I am having trouble with my key fob, the car will not unlock or lock unless the key fob is near the rear windows or rear glass, the battery is new. What could be causing this? I have 15% tint all around and 35% on windshield if that matters.

DaveW68

It could be an issue with the tint as most tint has metal which can reflect RF signals.

When I had my M5, my fob worked exactly the same way with almost no range. The Comfort Access (same as Keyless Go) was spotty to say the least. It turned out that the Diversity Antenna, which was located below and connected to the antenna fin was shot. I replaced that and my range increased to over 150 ft. Perhaps your Benz needs the same kind of part.

Garticus

You might want to check the car battery......I had a similar problem and it turned out to be my electronics supply battery (separate from the stater battery in the engine compartment) that was the culprit.

Low voltage was causing my key fob problems (I could not lock/unlock the doors or open the trunk with the key fob). I changed the supply battery (in my trunk) and all of my symptoms disappeared.

Denis_E55

I will give that a test. Thanks!

triniexr

I have a similar problem.... this is the 3rd car I've owned with the same issue.

2005 Acura RL, 2007 Lexus LS460L, and this 2011 Mercedes S63 AMG.

When the driver door handle gets wet it stops unlocking itself when you grab the handle. I have to grab the rear door handle to unlock all doors.