On 2010 and newer TDI models the ECU is secured down with tamper-proof bolts. Once removed, these bolts cannot be reinstalled, so new ones must be used. You will need to remove the ECU for chip tuning, so have these on hand when getting your car tuned.
Different cars require different number of screws. Jetta, Golf & Sportwagen models use two, new Passats require 4.
