For weeks I was trying to diagnose a problem with my 67 camaro with the turn signals not working. There are a couple of big things I wanted to share in the event someone else has similar problems. First issue was the Hazards worked in the rear, not in the front. This turned out to be a bad socket to housing ground on front parking lamp housings. Once I grounded the sockets the parking lights came on. Once I got the Hazards working, I discovered I had no turn signals at all. I checked every ground there was and cleaned them, still nothing. I replaced, matched bulbs, made shure I has the right fuse, checked flasher, still nothing. To make a long story short, make sure you have 12 volts feeding the turn signal flasher. If you have a voltage drop because of a long or wrong guage wire, or some other wierd happening going on along the wire, your turn signal flasher will sound like it is operational, but its not throwing power to the circuit.