Another vote for testing the horns. I was so convinced that the electrickery of relays and clock springs were to blame until I did check the horns themselves. Both had failed and a pair from Darren sorted it.
The only irritation is that the horn contacts are tiny.
RAC want £145 for my 2005 TF for a week in France. (With a clause that the cost of recovery does not exceed the market value).
What do others on here do for recovery?