Earlier on in the week it stated to come on occasionally; but by turning the engine off and on it would go away for a day or so. However now the problem has become permanent. I've already got it booked in to be checked. My questions are

a) What could be the cause - Dead pump/loose connection/fluid level?

Will I cause damage driving it?

Very common fault, a search would help more.

Could be...

Steering Angle Sensor

Altinator

Pump

Low Fluid

etc,etc,etc