Broken electric Aerial - won't retract :(

Hi there,
I'm a new owner of a gorgeous 2002 Phoenix 1.8 litre MX-5!!
There is a problem however with the electric aerial. It was working when I picked up the car at the dealership 2 days ago, but since then it won't retract.
When you turn the radio off, you can hear clicking sounds so something is going on somewhere, and using a multimeter there is power getting as far as the motor at least - where do I go from here without having to bring the car back to a garage?
What should I check and how do I check it?
Thanks a lot!
I'm a new owner of a gorgeous 2002 Phoenix 1.8 litre MX-5!!
There is a problem however with the electric aerial. It was working when I picked up the car at the dealership 2 days ago, but since then it won't retract.
When you turn the radio off, you can hear clicking sounds so something is going on somewhere, and using a multimeter there is power getting as far as the motor at least - where do I go from here without having to bring the car back to a garage?
What should I check and how do I check it?
Thanks a lot!