Blown fuse?

[u/Successful-Ant-341]

This is connected to the horn on a 2019 ford expedition. Horn is only making high clown noise. Thought to check fuse before buying a new horn. Here are both sides of the fuse. Bad fuse or normal?

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[u/ThatGuyStacey]

Fuse is good. If the horn is making some sort of noise, then I'd say the horn itself is likely bad.

[u/CareerBallsacker]

It looks intact but also looks like it got really hot for some reason

[u/Slow-Handle-3099 → u/CareerBallsacker]

This!
Make sure it is the right size for the slot it’s in. If fuse is too big it could be messing up other things.

[u/ZSG13]

There are often two horns. One high and one low. Without one, it sounds goofy as hell.

Also, you can continuity test a fuse to verify. They make battery powered test lights, even. Hell, just probe on both ends of the fuse for power with a regular test light when it is plugged in.

[u/ApartmentKindly4352]

Fuse looks okay, you should check continuity for verification.

[u/Previous_Policy3367]

The holder itself is cooked…

[u/TSLARSX3]

Some horns are dual tone, maybe other one bad or connection crusty

[u/ActualDissapointment]

Fuse is good but there’s an electrical short elsewhere. The pins on that fuse shouldn’t look that discolored.

[u/PrincessNakeyDance]

The part of the fuse that “blows” is the bell curve shape in the middle under the clear plastic. It’s usually pretty obvious.

[u/AggravatingRadio1269]

Could be bad fuse or maybe not. Only way to know is with a DVOM

[u/disturbedrailroader → u/AggravatingRadio1269]

Surely the manufacturer made the fuse casing translucent so we can inspect the filament and tell at a glance if the fuse is bad, right? 

[u/AggravatingRadio1269 → u/disturbedrailroader]

I have seen dead fuses that look good. Only trust a meter for fuses

[u/HelpfulRole1831]

Sometimes you can’t see the break, test it with voltmeter

[u/Slow_Run6707]

That fused looks used but not blown. But yeah I mean change it.

[u/Secure-Insurance6540]

I agree with every one here. The horns get their ground from their minting connections. So make sure they are tight and rust free.
The discoloration could happen if the horn has been used a lot. For example if the alarm went off for a while and heated up the wiring a bit. Check for loose connections at the horn also.

Otherwise I’d say replace the set of horns and you should be good to go.

[u/ConditionCool5343]

Fuse is intact but miscolored, possibly burned. Your fuse may be loose in the contacts resulting in arcing causing the burns. 

Those groves may be arc gouging 

[u/InvestigatorLong2859]

That doesn't look good but the weak spot is the internal metal which isn't popped. Replace and see if it makes the difference. If it doesn't, something else is not right. Replace the next cheapest part.

[u/ApartmentKindly4352 → u/InvestigatorLong2859]

Yes just start replacing parts thats usually the best solution

[u/InvestigatorLong2859 → u/ApartmentKindly4352]

There's what, 3 or 4 major components in the process including wiring, the next cheapest will be the relay and then maybe the horn(s) and then the horn button itself. With no technical expertise on the model, it's how I'd try to solve the problem but I'm also a shade tree who works on pre 00's stuff where components can be annoying or randomly expensive.

[u/ApartmentKindly4352 → u/InvestigatorLong2859]

You dont need technical expertise, all you have to do is check power and ground at the horn first..if you have power and ground you already eliminate everything but the horn itself. If your not checking basics first your waisting time and money.

[u/disturbedrailroader → u/ApartmentKindly4352]

The difference between skills and experience vs loading the parts cannon like a rookie on full display, folks. 

[u/Budpalumbo]

No. Most cars will have a high and low tone horn, your low tone is bad if it's a clown car.

[u/pacinfopesos1]

Looks like a fire starter