I have a DAF LF 45 and the wipers keep getting stuck?

I have a DAF LF 45 and the wipers have stopped working they made a low wining noise and went on for a little and stopped in the middle of the screen. The fuses are fine don't know if it could be the relay switches but don't know where they are. Can you tell me where the relays are or suggest anything else to check? Please

Tracy Macdonald
September 2017