Mystery Headlight Activation

I have a 2004 Hyundai Elantra that seems to be haunted. Occasionally, when the car sits for longer than 24 hours (which is often, I work minimum 72 hour shifts) my headlights and running lights will spontaneoulsy begin to flash. The keys are nowhere near, nobody has jostled the car, there is NO reason for these lights to be flashing. This has been going on since I bought the car. i tried changing he battery, and it still happens. Any ideas?

Sounds crazy, but check all of your bulbs for a faulty one. I experienced this with a Ford Escape…

I recently changed both headlights, and it still happens. Thank you for the suggestion though.

Unless your car had a circuit that flashes these lights by design for some reason (a look at the schematic or review of the owners manual is called for) you electrical system is shorting,not a short to ground but a short to the circuit that activates these lamps.

Seriously, the exact same thing?

Did you buy the car new? If not, do you know if a previous owner had an aftermarket security or keyless entry system installed?


Which lights are flashing? If it’s just the headlights which flash, swap the Hd Lp relay with one of the other relays. The relays are in a box under the hood. I’m not saying that this will fix the problem; but, it may(and, it costs $0.00 to try).

I did buy the car new. It has a factory installed alarm system and keyless entry. When the lights falsh, its all the lights. The headlights, all the ambers, my break lights, the back up lights, everything. They do seem to flash in a sequence though. They flash three times and then there is a longer break (Maybe 2-3 seconds) and then they start again. I tried turning them off with my fob (sorry if thats not spelled right) but the only thing that gets them to stop flashing is to go in and turn on the car.