96 3500 extended cab slt larami having turn signal problems..........if headlights are on, turn signal will not blink, only stays solid, if headlights are off then it works. i have changed the bulb, and checked fuses with no luck.....any ideas?

 

with everything off, try cleaning the bulb socket. make sure there is no rust, grease, crud, etc. it sound like your headlight 12v is bleeding over to the blinker. after everything is clean, then check the socket's bulb pins with a voltage tester. with the right switches on, headlight pin/wire should be 12v constant, blinker should blink. if socket doesn't test properly, then you'll have to work you way backwards. flasher iis in the end of dash fuse panel. it seems ok, but its not expensive to replace either.