First let me start by saying that this Mercedes is the finest automobile for the money that I have ever driven and I have driven them all...........so I have the tire pressure monitoring system and it worked fine until 2 weeks ago when the display said there was a malfunction and to "drive to workshop". I had never seen this message so I took it to Mercedes of Buckhead the next day. They hooked it up to the computer and fond some other problems as well as a bad sensor in the front drive side wheel. The technition replaced the xenon bulb and ignitor and the driver side and reset the TPMS system and said to drive it a few miles and it should restart correctly. Well 3 days later the system still showed a malfunction. It became very annoying because it locket out the steering wheel controls(found out later to hit the R button). Took it back on Tuesday and a new technition decided to replace the sensor altogher. Took it back on Thursday to have it replaced and was told to drive a few miles for it to activate......well after driving about 5 miles it activated and said there is a problem with the TPMS and to drive to workshop.......geeesh! So I will take it back again but was wondering if anyone out there is familiar with the system or has encountered a similar problem. The car is still under warranty for another year so cost is not an issue......it is that I pamper this car like my first born(on the way) and it drives me crazy to see a malfuntion in the dash!