Finally managed to get my dash working again.
I found a reset method which has cured the problem.
It's called disconnection of the battery for 15 minutes.
I decided to remove the after market wiring for the electric fan, and whilst doing this I needed to disconnect the live terminal. And once I had done, and all was back together. The dash was working again, and has been ever since.
And I am no longer getting a static shock every time I get out of the car.
Which is a win win in my book.