I have a 1987 Pontiac Firebird that has a fuse that keeps blowing. The fuse controls the radio, flashers, dome light and horn. When trying to replace it, it instantly blows. Once in awhile you can get it to stay on for a couple months, and then something happens and it blows again. Any advice?

Question edited for clarity, 'fuse', unless you light it 'fuze'.Question moved to sub category.

If the radio has an inline fuse, it will be within 82 of the plug at the rear. They are built into the harness. Unlikely because there are three fuses covering audio.

https://fuse-box.info/isuzu/isuzu-trooper-1992-2002-fuses-and-relays

C11 10 (AUDIO[ACC]) MIRROR Audio, Door mirror, Door mirror control SW, Door mirror folding SW, Digital clock, Speaker C12 20 CIGARETTE Cigarette lighter C13 10 ANTI THEFT Anti-theft controller C14 15 STOP A/T CONT Stoplight SW (w/o cruise control), Brake SW (w/cruise control), Rear wheel anti-lock brake controller, Stoplight, Transmission control module, Electronic brake control module, Trailer harness connector, Cruise control unit, A/T shift lock control unit, Lockup off relay C15 20 AUDIO[BJ] Horn, Horn relay, Horn SW, Hazard warning light SW, Flasher unit, Anti-theft horn, Hazard warning light, Audio C15 20 TELEPHONE Telephone C16 10 CLOCK[B] ROOM Digital clock, Audio, Dome light, Map light, Luggage room light, Courtesy light, Door SW (Front, rear, tail gate), Antenna, Anti-theft controller, Key remind SW, Seat belt, Key & light remind buzzer

Fuses blown is the most likely. The gauges fuse has a lot on it.

Pontiac Firebird (1999 - 2002) - fuse box diagram - Auto Genius

www.autogenius.info > pontiac-firebird-1999-2002-fus...

Mar 11, 2017 - Pontiac Firebird (1999 - 2002) - fuse box diagram. Year of production: 1999, 2000, 2001, 2002. Instrument Panel Fuse Block. Pontiac Firebird - ...

there might be corrosion on the ends of the fuse holder check that or try tuner cleaner before inserting the fuse.could also be a short in the fuse holder.

fuse 17 looks like it operates the brake switch/brake lights/ and audiable alarm system. go thru the elimination process such as brake bulbs first(take out) see if fuse pops.after applying brakes the hazard-flasher is on this circuit as well so if u have a tilt steering wheel make sure wires are not frayed inside steering wheel column as well. from there it goes to the audible chime warning module..hope this helps

I had a camaro that did something similar but different. This one would run and start, but some thigs quit working. There was a fusible link down by the starter that burned out. I replaced it and everthing was fine.

Try a turn signal flasher , it's different then the 4 way flasher. You may have a bad horn too.

First place i would look would be the radio, especially if it's an aftermarket installation. You will have to pull it out and look for loose broken or bare wires.

Check inside the drivers and passenger side door jam for the little push in type switch. 9x out of 10 one or the other will be causing the short to the dome fuse. These little **** get rusty and also get alot of wear and tear from the door opening and shutting over and over. These switchs are what causes your dome light to come on when you open your door and or likewise they shut your dome light off when you shut you door. A very good way to test to see if one of these little switchs is the couprate is to take and hook up a voltage light into the negative side battery post after you disconnect the battery negative line.. If your voltage light is on than that would mean that you have a short somewhere in your system. Now, since you already know that you are blowing the dome fuse then your already halfway there. With the light on your votage light still on indicatin a short, unscrew the little switch on the door jam and disconnect the power wire from it. Check to see if the light on your voltage light is still indicating a short, if not then you can be sure that the door jam was the coulprete. Hope this is of help.

i have been shoping on ebay for years looking for parts to restore my t/a's and just noticed that shopping online with year one and national parts depot, i've found the parts somtimes brand new at cheaper prices. also i've been lucky to find parts at my local pontiac dealership for my 1987 gta trans am. hope this helps.

The horn and the flashers are controlled by the 15 amp HAZ-Horn fuse.
The trunk light is powered by the 20 amp Dome light.
The radio is powered by the above Dome fuse, and the 15 amp Radio & CIG fuse.
With a 12 volt testlight, check for power on BOTH sides of the above fuses. If you have no power to either side of the fuses, you have an open circuit under the hood that feeds said fuses: Look for an open circuit in the main fusible link coming right off of the battery positive terminal to the wiring harness.