I have Audi A4 2.0tdi which does not start. The vehicle went over speed bump and switched off. Fault codes P1517 Main Relay Circuit Defective and P 2146 Power Supply Injection Valves Bank 1 open circuit recorded.
Do you live in Europe? Here in north america they never sold a 2.0L TDI in a 2004 audi a4. Either way, the fault is for the power supply relay for the ECM J271 or J363 (whichever one is equipped in your vehicle). The possible causes are the relay itself, the harness/circuit between the power supply relay and J271 or it may be as simple as the fuse that supplies power to the relay.