I have an issue with both engine cooling fans remaining on, at high speed, for some time after the engine has been switched off. This can go on for 10 minutes.

The dashboard engine temperature indicator is normal.

I'm guessing this might have something to do with the AirCon?

Any advice would be very much appreciated.

My first port of call will be to remove the Aircon fuse.

It's till the same with aircon fuse removed, have noticed a small leak from somewhere and the coolant was running over the fan speed controller connection. I guess that's what's causing the issue.