hot headlight switch
 

Anybody know why my headlight switch would get hot enough to desolder some of the circuits? I have resoldered them twice, checked for short circuits and found nothing. I just changed the switch and the replacement is doing the same thing.

I know someone has had this happen to them. I would appreciate any answers you might have.

check for burn marks on your wiring harness. I smoked(yes smoke was coming out of my dash where my harness and switch were melting together)my switch and harness.

yeah, that happened before and I replace the wiring harness. that was about 5 years ago though. I can't determine what is causing the heat build up.

They should not get that hot.

As mentioned above, that is a good indication that the switch/harness is starting to fail.

Check all the bulb connections at the bulb as well. Chances are that you have a few that have some corrosion on them which is adding to the problem.

1. Mazda headlight switches suck

2. Mazda wiring harnesses suck

3. Do what everyone else said. :) Also, make sure you are soldering correctly. It's really easy to make a bad joint, but takes practice to make a good one.

No... owners that don't take care of their cars suck.

90% of the time when I see a light switch that has burnt up be it in a Mazda or any manufactures product (well except for Hyndai, but that's another story- their products really do suck) it is related to a bad connection at the bulbs.

Go out and check the condition of the bulbs and sockets on any 15 year old car and you are gonna find a couple with that white corrsion crap growing right out of the sides of the bulb or socket.

Well when you get enough corrosion built up, you'll find that the current requirements just to light those bulbs has slowly built up as well.

To top that off I bet more than 75% of the bulbs are the OEM ones with their smoke faded glass and worn down conductors.

So how can you expect a switch that was designed for a 7.5 amp load to be able to work at 100% duty cycle every time you turn it on??? The fuse won't even blow until a draw of 8.5 amps goes through it. (ATC fuses typically have a 110-115% blow current rating).

Now it used to be pretty common for better mechanics to use a little conductive grease on any bulb that was replaced, or that was expected to be exposed to the elements. If you have ever had problems with the light switch burning out, I betcha you haven't replaced your bulbs or cleaned your bulb sockets.

Yeah the old "hyperblinkers" or "blinking headlights." Time for the wirebrush.

thanks guys. I'll check the bulbs, but I replaced them less than six months ago, just for the heck of it. The old ones had been in for years. I hope, for simplicity sake, that there is some corrision on the bulbs.