Hello, Bit of an Audi newbie, Was so impressed with my wifes A3 Quattro I just bought my first one - an A4 2.5 V6 TDi. Its a 1999, all the mod cons............ Except the ABS ECU is missing, not sure why - the harness is there and looks alright. The brakes arent affected at all (other than the ABS obviously) the Dash display has a nice flashing exclamation mark - albeit badly pixleated! My question is will any ABS ECU from another similar aged A4 fit and do the job? And will it be as simple as plug in and go? . Thanks!