Intermittent speedo

[Ajelectrics]

Hi, iam new to the forum, I have a 57 plate berlingo van and for the last year it's had a fault with the speedo, just randomly stops working, maybe for a minute or sometimes longer? There is no reason it does it, can be straight away when it's cold , hot? My first thought is a speed sensor. So I managed to get one, went to change it the other day and can I find it, I looked everywhere. Any ideas as to the location and if iam looking at the right thing??


Thanks