Replacement engine causing electrical issues AUDI A6 C6 Allroad (4FH) (05.2006 - 08.2011)

My cam chain snapped and basically smashed the engine to bits, so I bought a replacement engine from a breakers. I fitted it myself in my driveway. It fired up first turn of the key and is a really sweet engine. After driving a couple of miles the brake warning lights, the esp light , the ABS light all came on and stay on but the brakes work perfectly, also the turbo actuator only gets a signal intermittently and the heater plug light comes on when turbo not getting a signal. Turn ignition off and on again and the turbo works fine for a few miles more but the rest of the above lights stay on permanently. could this be something to do with the ecu not recognising the replacement engine?