Can you please clarify the symptoms? I'm not sure how to interpret, "an when I dont drive my headlight are brandnew".
If the head lights flash off while driving, then come back on a short time later, that is almost always due to the head light switch, but there are a few other things to look at too. The switch contains an auto-resetting thermal circuit breaker. Those cause more problems than they prevent. Over time the contacts become pitted from arcing, and the spring tension goes away. Normal current can be sufficient to cause the circuit breaker to trip, then it will reset a short time later, on its own.
When you pull the switch out, look closely at the connector body to see if a part of it is melted, and if two terminals are black or overheated. If you find that, the switch must be replaced, but the new one will fail shortly too if those terminals are not replaced. The easiest way to do that is to cut the old ones out of the connector, then replace them individually with a pair of universal crimp-style terminals. You will also find the first four inches of wire is hardened from the heat. Solder won't adhere to that, so you need to splice in four inches of new wire of the same diameter. Solder the splices and seal them with heat-shrink tubing. Never use electrical tape for that as it will unravel into a gooey mess on a hot day. Also solder the terminals to the wires after they've been crimped on, to insure a good connection.
This problem of overheated terminals can happen to the dimmer switch too, but it is less common. In that case a potential clue is when the head lights cut out, the high beams might still work.
Monday, November 16th, 2020 AT 8:43 PM