I have caused a similar type of thing when I was trying to sell my late parents house.
The house was empty but I rigged up a light run off a timer that would come on at night and go of in the day time.
I was very late going round one day to check on the property (having lots of windows smashed by the local kids a few weeks earlier) and it was dark.
Going up the drive I was confronted by a white flashing light
, I had a look around the outside first to see if there was someone in there, it looked ok, so I let myself in and was confronted by this light flashing on and off just like morse code.
Peeping around the door, It was only my light on a timer that was flashing .
If only I did not put in that low energy light bulb to save on the electric bill.
It had come to it end of it life and like most fluorescence lights it flashes on on off trying to strike.
A neighbor said it been doing that for ages ( I did not know because I would normally go around in the day time).
