I have a 72 Cutlass S and the turn signal/back up/seatbelt fuse is out. Trying to see if anyone has had the same short problem. I've unhooked the wiring to the back under the steering column, so I know that is not it. Since the seatbelt warning is hooked up to it, I get to hear the great buzzing sound also. What a treat. Just hoping someone might have a suggestion to this nightmare.
the fuze shorts out as soon as I turn the key on.

 

This may be a long shot, but I had a 70 442, that did the same thing. I looked for days to find the problem. Not sure if your wiring is the same, but on mine, there was a wire the ran along the pass engine top, and was conected to a wire that went to the transmission, turbo 400. Anyway I had the valve covers off about 3 mounths before, and when I installed them, I got the wire stuck under the valve cover, and after a while it wore through, and cuase a dead short. You need to get a good wire digram and follow through all the wire conected to that system till you find it. You probably have a bare wire. I had my son help me and it works better with two guys, and takes time. good luck. I have also learned if you come up with a problen that was not there before, go back and think off the last repair or thing you did to your car, and see if they are related?

 

Is this a floor shift or column shift?

If floor shift, the switch that controls the backup lights is in the console. It is tripped when the shifter is moved to the 'reverse' position.

Blinker problems can be an altogether different problem. The blinker canister is probably up under the dash. At least it was on my '72. The silver can on the fuse panel is the hazard flashers.

Bad lights and gunked up lamp sockets were most of my problem. A shorted lamp can blow the fuse too. I replaced all the lamps and cleaned the sockets and the blinker probems disappeared on my '72.

You can disconnect the seat belt switch. There is a plastic connector under the seat. See if the fuse blows with the seat disconnected.

There is also a connector in the trunk that will allow you to disconnet the rear lamps. It shoudl be right along the rear of the trunk under the trunk lining.

As the other poster mentioned, if you have done any other maintainance recently that may be a place to start.

Good luck!

 

It is a column shift. I know it is not the seatbelt or the lighting in the back of the vehicle because I unhooked all the lighting to the rear(which is also to the seatbelt) under the dash and the fuse is still blowing. Someone did email me and said it might be in the turn signal wire that is in the steering column, so that sounds like that could be it, just not for sure til I can take the steering wheel all apart.

 

I wonder if you pulled the flasher out, and see if the fuse still blows? I don't know if that would open the circuit from the switch to the bulb, but thinking it would, that might pinpoint it to the turn signal being the problem, anyway good luck.