what do i need to do for codes p0455,p0422 and p1747

P0455 is gross emissions leak,P0422 Main Catalyst Efficiency Below Threshold (Bank 1),P1747 Electronic Gear Selector Module: Defective Interaction of CAN with control unit A1(instrument cluster). Not much anyone not familiar with Mercedes repairs and proper scan tool can do. Is there a good independent Mercedes repair shop near bye?

fro your code you can try this: Remove and reinstall the gas cap, clear the codes, and drive for a day and see if the codes come back. you can use the elm327 to clearn the code. http://www.chinasinoy.com/wholesale/usb-elm327-v14-plastic-obdii-eobd-canbus-elm-327-scanner-free-shipping-1297.html Otherwise, replace the gas cap, and/or Inspect the EVAP system for cuts/holes in tubes/hoses (you may hear a vacuum noise or smell fuel), repair if necessary