Towbar now removed and much easier access to the locking mechanism. At ground level it looked to me like the key had been sheared off in the lock but on the bench it was just the dust cover.

As I didn’t have the keys I contacted Towequipe as they hold a full set of keys that they will hire out for a refundable £150. But before ordering I had a further think… where would I keep a set of keys that will not fit on a key-ring (like the Westfalia “button” keys)?

I had a feel at the back and underneath the storage compartment for the towbar in the boot and Eureka! I found a little plastic bag with two keys and a plastic dust cover!