Thanks for the input, but none of the working turn signal flashers are chinese. They are from the scrapyard, tow. If the trouble goes on. Ill try to disconnect one by one of them.
One more thing, by the way! One of the lamps is a LED lamp. and first I wasn't aware that ground and plus must not be mixed on LED lamps.
When the fuse blowed, I had this mixed up. I thought is was none working. Maybe this can create a small dead short tat after a while will blow the fuse?