I have a 2000 Mazda Protege ES, and at times, the power door locks malfunction. When the weather is cool or mild, the locks were perfectly, but when it is very hot outside, they malfunction. Some will lock/unlock and some won't. It's different locks each time, but overall, all of them malfunction. Since the work at times and don't work at other times, I think it's not the actuator. I tried a new door lock relay, but that didn't help either. Any ideas? Could it another bad relay?