Hello, new member who on the Jst July exchanged my C220 CDI Estate for a 2002 SL500. Having a few warranty issues, keyless go drivers/passenger door buttons not locking the car, but boot button works! All other keyless functions working. And a fuel Guatemala that reads full goes down to 1/2 as normal but then drops to empty! When I first drove gingerly to pumps I could only get 30 ltrs in! Need some advice about the ABC system Please