I have had a search through previous posts and I can see it is a common problem.
I just wondered if there was a way that I could work out whether it is the fuel cap solenoid or the door switch causing the problem?
Before I start considering replacing parts of booking it into a garage.
Thanks Andy

Try disconnecting the power cable to the tail gate and fuel flap motor in turn if the fuse doesn't blow when the tail gate is disconnected then the tail gate actuator is faulty. Same goes for the fuel flap Solenoid.
I had to fix a Peugeot 306 2.0 hid once which had the battery light on all the time. I tested the battery alternator to find both was working as normal. I noticed the rear wiper was parked in the middle of the rear screen rang the customer to find that it stopped working. Checked the circuit the fuse had blown for the motor. Replaced the fuse it blew again so unplugged the electrical plug and refitted the fuse guess what the battery light went out. It always pays to do some manual detective work.

Highly likely its the tailgate switch full of water thats causing the fuse to pop?

Cheers, think I'll take a look today, I read on another forum you can pick up a replacement switch from Maplins.

It all came apart and went back together easier than I expected.
I soaked the switch with GT85 to displace moisture and cleaned and lubricated other parts.
So far no fuse blowing, so fingers crossed it will stay that way.

Well fuse blew again today and fuel flap will not open with new fuse.
It looks like a new fuel flap actuator is required.

More than likely this is your problem.

http://www.freel2.com/forum/topic17008.html p****d off with a Digital Keyboard Warrior

I bought the fuel flap actuator and it will be fitted tomorrow when it has it's annual service.