For some reason all of a sudden,I keep blowing fuses everytime I turn my blower fan on. It is ok when the ignition is on, but when I turn to the next speed, the 25 amp fuse blows. Everything was fine last week. Anyone ever had this problem ?

Well, I finaly found out what was causing my fuse to blow when I turned my a/c on. Traced all my wiring back to the heater control and couldn't find any short. Check this,checked that and still couldn't find anything wrong. As I sit there looking at my wiring diagram in my repair manual, I notice this thing called a stop idle solonoid (on front of carb). Disconnected the wire that goes to the solonoid and presto,it worked.Forgot that the solonoid controls the idle speed when the a/c is on when your at a stop. (new solonoid $43.00)Think I can live without it till next summer. Now I'm ahappy camper.

Unplug the blower resistors and try again. If it stops blowing fuses you have created an open circuit, and the problem is at the resistors, or after them in the circuit.

If it still blows the fuse, you have a wire shorted between the blower switch and resistors. This seem more likely.

In either event you might narrow it down by turning the blower switch to high position, the turning the key on. If the fuse does not blow, turn the switch down one click at a time. When it blows that is a key to following which wire from the switch to locate the short.

Give it a try and let me know what happens. Well go from there.

Hey Ken
I pulled the resistor connection and it still blows the fuse. If I slide the selector from off to the warm or vent side, the fuse blows. Have reason to believe it's in the ac compressor. Won't know till I go buy more 25 amp fuses. Also, noticed that on my fuse box, there is a aux fan fuse (30 amp). What's a aux fan for? The fuse was never put in. Thank's for your help

rear window defogger

By sliding the selector and having the fuse blow, unplug the compressor and try it. Also look for a short in the area of the heater control head. You could be shorting to ground in the controller area. You may want to pull the side or top of the console and take a look.

maintenance4 said:|What's a aux fan for? The fuse was never put in. Thank's for your help

79 and 80 L82/AC Vettes were equipted with the additional electric cooling fan. Only with the L82/AC.
Mike

Hey Ken
I think your on the right track. When I slide the control from the heat or vent side to the cool side is when the fuse blows. So it's either in the control switch or possible in the relay. Will check further this week-end. My backs sore,my knees are sore and I need more fuses. Who's idea was it to put the fuse box up under the dash??I'm not getting any younger. (all three speeds work on the heat side)Thank's for all your advice

That's good information. That means the blower circuit is okay. The fact that it goes to cool, then blows means something in the A/C circuit is shorted, and causing the fuse to blow.

Before taking the console apart, look under the hood at all of the A/C wiring. Check it for bare spots or shorted wires.

Unplug all of the A/C components under the hood. If the fuse still blows, it's in the control or the wiring. If it does not, start connecting the components one at a time until it blows.

The part you plug in may not be the problem, but it may feed something that is. So plug in the compressor last.