Apple wireless keyboard problem

My 24" iMac and aluminum wireless apple keyboard is over 2 years old. I recently noticed that the left arrow (navigator key) won't work. I used the keyboard viewer and confirmed that the key does not highlight when I press it.

I suspect that the key is bad and was wondering if there was a way to remove the key and clean it or some way to open the keyboard to clean it.

Regds

Here's a LINK with some pictures showing how to remove the key caps to clean underneath.

Thanks

Managed to clean the keys, but it appears that the key connection on the board is faulty