Flickering lights


#1

My car recently just started to flicker its lights on and off continuously and won’t stop unless I shut off the car but then once I turn it back on about two to three minutes latter it starts again. It only does this at night time, and I have automatic lighting


#2

Does anyone know what might be the cause of this, is it an early sign that my alternator is going bad, or a bad fuse, or poor connection from my battery to my car? Any input would be helpful!!! Thanks!!!


#3

Year make and model please?

What do you mean the lights are flickering? Do they turn on and off by themselves, or do they just vary in brightness. Which lights? Headlights? Instrument panel lights? Warning lights? Taillights? All of them?


#4

Two likely possibilities. First is the auto-light sensor which determines whether it is dark or light outside is faulty. It might just be dirty is all. If you can figure out where it is, try cleaning it off. Second is you have a short circuit somewhere and a circuit breaker is turning the circuit on and off.


#5

My first choice would be the alternator. I had one do that and it tested fine but when I replaced it the flickering was gone. Also could be a bad connection. If it were the auto lights, I suspect it might be blowing the circuit breaker so the lights would go out for a few seconds while the breaker cools, and then come on again. Had that one too and just disconnected it and all was fine. No fun to be driving in the dark and have the head lights go out. Does it make any difference if they are on low beam or high beam though?


#6

Third possibility: a failing alternator. Specifically the rectifier in the regulator portion.
For the record, I’m betting it’s a bad alternator.


#7

I’m also voting for a bad alternator. I’ve seen this problem over and over for years and the fix has always been the alternator. Many years ago it was a voltage regulator problem but since the regulator is generally part of the alternator now…well you get the picture.