Left turn signal works on front but not in back

SOURCE: I tried replacing the right rear turn signal

The circuit boards in Chevrolet tail lamps ar notorious for going bad. Dorman makes a replacement circuit board, part number 70006 . the same part number will fit either the left or right side of your Trailblazer.

SOURCE: left rear turn signal light on my 1999 chev. s10 is not working

any increase in bink speed is direcly related to a bulb being burt out.

SOURCE: Chev Cavalier 2003 only one rear turn/brake/hazard light

I have a 2002 Chev Cavalier that had the same exact problem. I replaced the bulb harness (purchased from a chevy dealership for around $5) which was fairly easy to do. I have had zero problems with it since.

SOURCE: left turn signal problem on06' chevy tahoe

check your left light fixture.make sure you have a good contact.sometimes they burnout

SOURCE: Left turn signal blinks fast in rear and regular in front

the bulb is blown out. you need to change it. also if the bulb is not blown out or if the blinker still blink fast after you change the bulb then you have a ground problem. just remove that blinker light and check the ground wire on it. if you need to replace it and find a good groun on the car. you should be fine. this is all it is .