windscreen wipers working intermittently.

[PlasticMac]

So relay changed and absolutely nothing moving in the wiper motor. What autos be the next best thing to check and what is the easiest to check?

I’ll add a third Earth to the motor in addition to the one that I added years ago and is it worth having a check of the main Earth under the headlight?
Then it’s
Motor
Stalk

What else should I check?

You need to check if there's a 12 volts supply to the wiper motor, with the wipers switched on. (Good idea to remove the wiper arm, to avoid damage/injury, if it moves). If there is, the motor/gearbox is at fault. If no 12 volts, work back, via relay, fuse etc, to find out where it is being lost.
Mac.