Took my white roadster out today for the first time in a while and got a strange electrical issue with the wipers. They are coming on automatically.

What I have found is happening:

1. Anywhere below approx 30mph and the wipers stay off.
2. Anywhere between 30mph to 50mph they stay on and also activating windscreen washer bottle (so that's now empty!)
3. After approx 50mph they wipers, etc go off again.
4. Around 2.4k rpm with the engine warm I can simulate the same problem while stationery.
5. As per point 5 problem doesn't seem to happen when engine, etc is cold??

Any ideas?? I changed my steering wheel and boss recently so thought it maybe that but taking that off and problem still remains.

Any help would be appreciated. Done a search on here and google but not come up with anything.