V50 Electrics : Speed sensor problems

[Aaron6]

Hi all. New to the Volvo world. Always been into my old peugeots. Well, i still am, the Volvo is for the wife.
Anyway, we got a 56 plate V50 a week ago which had a wheel bearing going so we changed it and lovely, the rumbles gone. However, we had the abs and anti skid alarms come up. So thinking we've damaged the sensor we changed it for a new one. Drove up the road, the lights went out but the speedo was reading 25mph when I was doing more like 60mph. Very odd... then then the lights came back on, the speedo read correct and I was back to square one.
Today the wife messaged me to tell me the lights are still on but there is no reading from the speedo.

Any ideas?

Is there a way of recalibrating the new sensor?

I've read up and this seems a common issue and has something to do with a control module? Dodgy solder or something? Seems strange though as it was perfect before the wheel bearing was done.

Plugged it into my mates reader which would read everything but things to do with the abs sensor it couldn't see.

Any help is much appreciated.