andrewclaus wrote: ↑Mon Jul 08, 2024 4:26 am
I'd first check for corrosion at the bulb sockets.
I agree. The hyoerflash is a feature of the flasher relay, it senses there is not enough current draw from the lights and flashes fast to let you know you likely have a burned out bulb somewhere. An issue for people who switched to LED bulbs, which draw less juice, but that's not your issue.
Since it happens intermittently, you could have a bad connection somewhere. It also could be one bulb that has a broken filament, sometimes it flops correctly to hit make a connection, other times it doesn't. Might not be a convenient thing to do, but if you can, the next time it goes hyperflash, pull over, put it in park with the lights flashing, get out and see which light is out. Or you could replace the bulbs
I wouldn't expect the flasher relay itself to be a problem with those symptoms. It could be, but a bad bulb or other intermittent connection would be much more likely