left turn signal not working
 

hello this is my first time on this site.i have a 2000 chevy s10 pickup.when i turn on the left turn signal it makes a buzzing noise under the dash from the turn signal relay.and it blows the turn signal fuse.when i turn on the right turn signal it works but seems to blink fast.ive gone threw many fuses and i changed a few of the turn signal bulbs.and got a new turn signal relay.i also replaced a ground under the back bumper in the harness and cleaned up the other side ground.it still buzzes and blows a fuse ever time i try the left turn signal i checked all the front lights with a meter.they all seem ok.i bought the truck with this problem a few weeks ago.any ideas on what could be the problem?