Crank sensor reset on Audi Coupe B4

Hi my girlfriends got a 1993 Audi coupe B4 2.3e ng engine which doesnt start due to no spark. We did have the car running when we bought it but it just stalled and never sparked since. Weve put new plugs, leads, dizzy cap and rotar arm on it. Weve replaced all the coolant sensors and oil sensors but still no spark. Weve tried the coil and coil module on my B3 coupe with the same 2.3 ng engine and that started. Weve both come to the conclusion that the no spark has got to be due to a faulty crank sensor or a faulty ignition pulse sensor (hall sender) which is located inside the distributor. We finally located the crank sensor with a lot of research and help from the forums. We got the new crank sensor and fitted it today but still no spark. We wondered if a fault code may be showing in the ecu and need to be reset before the new crank sensor will work if that is our problem. Recently we bought a vgate scanner which is for Audis and Volkswagens of our cars era but have tried it on my girlfriends B4 coupe and my B3 coupe but both read not responding. Were not sure if the scanner does not work on our cars as advertised or we have the incorrect cable. Could anyone please tell us if we need to reset a fault code in the ecu for the new crank sensor to work if this is the fault or give us any advice or tips how to get the vgate scanner to work as this could really help us solve the nospark issue on the car. Thanks Ian!!!