So there I was fast asleep at 2:30 in the morning when I awoke to a noise. I walked through the house and soon realized that it was coming from one of the TR7 so, in my bathrobe, I ventured out into the pouring rain to discover that the 1976 TR7 DHC's horn was blowing all on its own. I quickly disconnected the battery and promptly went back to bed.
Yesterday I discovered that the horn relay, which is located in the engine bay, had filled with water and shorted out.
It was hanging by the wires and pointed down with the connector plate facing up. The water must have run down the harness somehow or another. It melted one of the spade connectors right out of the plastic end plate.
I have now attached the new relay by the metal mounting tab with the connector plate facing downward. Hopefully no more late night emergency repairs.
Edward Hamer
Petaluma CA