Windscreen wash won't turn off.

Roanmore

I'm driving a 2012 Mondeo.
Last week I was driving over some speed bumps in work car park (not going fast) and the boot opened and the back windscreen wash came on and wouldn't go off.

I parked my car and turned it off. Closed the boot. I restarted the car, everything good.
I then put on the front washers and couldn't turn it off. I had to stop the car again, turn off the engine and restart it which stopped the water flowing.

Later on when driving home I tried the washer whist stopped at lights. It came on for about 5 secs and stopped itself which would wouldn't be normal.

Since then it is staying on full time and the only way to turn it off is switching off the engine which isn't ideal

Anybody any ideas?

scannerd

Would guess sticking micro switch in the stock, except for the speed bump thing, which more likely damaged wiring / connector which is getting full time power now, when it shouldn't be.