Whats the fuse called the horn under the hood ? the horn fuse 3 prong is missing where can i find it

The Horn is fuse #8 in the under hood power distribution box, it is a 20 AMP yellow fuse. I think you will find the fuse is ok and the problem is the rotating horn contact (called the clockspring) under the steering wheel that is defective

most fuses are in the engine bay depending on what side the steering wheel is it should be in the engine bay just under windscreen when you take the lid off the fuse box under the lid there should be a plan telling you where each fuse is located on the board

LOOK INSIDE THE DRIVER Side DOOR UP on the left side there should be a black plastic box approx 3in. x 4in. under the dash area on the side open that box get a fuse tester there cheap there lil plastic tops with 2 flat cooper prongs I just get a box of mixed fuses and try to replace them 1.@ a time there usually marked start with accessory's on some older cars/ trucks there under the hood right back side drivers side

It more than likely under the hood. It is a 3 prong relay. Most relays have 5 or so prongs, so look for that. Also you normally find a cover over it and the underside shows details. You have checked fuses right?

horn relay located on the right side kick panel,you will see a row of relays,if horn relay is okay, more likely your horn control pad has a short inside causing horn button contacts to stick causing horn to keep blowing.

There are 3 fuse boxes on an '03 Alero. The block with the horn fuse is under the hood. If you're at the front of the grill looking under the hood, the fuse box is on the drivers side closer to the windshield. It is rectangular (about 6" by 8") and has a fuse symbol with a little lightning bolt on it. The star knob is the only thing that holds the cover on.
The horn fuse on mine is #21, a larger gray 4 prong fuse. Good Luck with that one.

There will only be one fuse for the horn. Find and check the horn relay. If that works check the wiring and the horn switch..

there should also be a srs light on the dash illuminated?! the problem is the clock spring behind the steering wheel. happy holidays

If you can hear the relay clicking then the fuse is not blown and the horn button is working. The horn itself is bad or has a bad ground. My guess is you need a new horn. klaxon horns rust on the inside and at some point quit working. Buy a universal replacement as original GM horns are very expensive.