One night in July, my car horn started honking intermittently. My neighbor disconnected the horn to make it stop and I later had the horn fixed.
Not much time later, after not driving the car for 3 days, my relatively new battery was dead.
Recently my neighbor noticed that my car lights would flash for a few minutes and then they would stop. (That would explain the drained battery.)
The repair shop wants me to leave my car there so they can observe the flashing lights. Could there be a loose wire causing this? Would that have happened when the horn was fixed?
Even though the horn was disconnected there may be a relay for it that is still turning on when the trouble happens and putting a small drain on the battery. I would guess the problem is with the horn switch in the steering wheel.
The flashing lights are most likely due to the alarm system being tripped somehow. This trouble may be related to the horn issue. A faulty door switch connection could cause the trouble or perhaps a bad power connection the alarm system may be the cause also.
I agree with Cougar. The first thing I thought of was the security system, and that the relay that originally made the horn beep was still energized.
Remember too that you may have a security feature in your key FOB with which you can press an “intruder alert” button and honk the horn and flash the lights…I do. It’s possible that the key fob is triggering the problem. It may even be a weak FOB battery, although this idea is a wild and unlikely one.
One more thought: until I modified my key FOB, the coins in my pocket and/or the other keys occasionally used to press the “intruder alert” button and activate the system, especially when I sat down. It might be as simple as that.