Re: (Lunchman)
I had this problem in very warm weather (close to 30 degrees centigrade) - the warning triangle would come on when I drove it with the message that the hood was open.
I took it to the dealer - he said that a sensor was probably stuck, and that he would clean it. I took it home and wiped them clean, The problem was that the dealer had put rust proofing all over and that was probably causing the problem.
The sensors are easy to locate. If cleaning them does not help, one of them is defective. But as I see, your problem is already solved.