car horn

Home  \  Repairs & Maintenance  \  car horn

i need to know how to fix the horn on my 1993 toyota corolla. if anyone knows how PLEEEEEASE respond. My car won't pass inspection without it.

posted by  wannabecarhass

could be a dodgy switch, dodgy wiring or a dodgy horn unit ... or a fuse?

posted by  windsonian

a ha! i figured it out. my grandpa informed me there was a fuse for it..but it didn't say that in the owner's manual. the fuses are fine. they click when you hit the horn and it just won't beep. so the horn is out.

posted by  wannabecarhass

That is a relay, and it might be bad. Check the horn by connecting a wire to the positive teminal of your battery and touch the other end to the connector on the horn. If the horn works then you need to check the wiring for voltage when the switch is engaged. And some auto parts stores will check the relay for you, for free I might add.

posted by  srober32

relays click, not fuses. so there may be an interposing relay between your switch circuit and your horn circuit. that means there still could be a dodgy wiring or bad fuse in the horn circuit. I'm not sure why they'd do it with a relay, but if it's clicking, then that's probably it.

posted by  windsonian

Because they can? :laughing:

posted by  srober32

keeps the service department with jobs i suppose.
It just doesn't make sense to have a relay in a 12V circuit, with 12V on both sides of it. Can anyone explain?

posted by  windsonian

hmmm, well as i understood, a relay is used for a small current ciruit to activate or deactivate a large current circuit, isnt that why relays usually have one or two thin wires and one or two thick ones :ohcrap: , am i wrong cuz if i am please tell me

posted by  BanffAutoSpa_ap

i'd have to say that is correct, and i figure that the automakers don't want too much current going through the thin wires and sliding contacts in the horn button assembly (i suppose they might weld themselves together) and that's why a relay is used. if you hear the relay clicking, it is probably working and the horn itself is bad. use a test light at the horn wire to verify this...

posted by  dodger65

That is what a relay is for. Often they are used for switching larger voltages too. For example, you might want to use a low voltage (eg 12V) control circuit to switch a 240V (I think it's 120V or something in the US) lighting circuit, or something similar.

I wouldn't have thought it necessary in this case, I'd have thought that it wouldn't be too difficult to rate the wire and switch for the horn to pass the required current.

But the way it would be working is:

press the horn switch, this closes the circuit, putting 12V across the primary side of the relay. This causes a switch to close in the relay (electromagnet I think) that then completes the other circuit, putting 12V across the horn.

posted by  windsonian

Did you buy the car used? Does it have an airbag? If it's supossed to but doesn't that gap in there can cause a horn not to work. I am coming across this problem more and more lately. I've noticed that there are still quite a few shops that will just replace the air bag cover and not the bag. If it does have the bag you will want to be careful removing the cover. If you do it wrong the bag can inflate.

posted by  staceymommy

The switch in the steering wheel is working because the relay is clicking when the switch is depressed. :banghead:

posted by  srober32

You did check the wire feed directly on the horn itself right? lol

posted by  Juhosaphat

alot of times the horn is mounted in the front bumper where it gets abused by water and rocks and road salt, if you can pull it out look at the connector it will probably be all green and corroded, then b4 you buy a new one, get your test light, hook it to the bumper and connect it to the power wire, your friend hits the horn and bling light goes on nice and bright then you go out and buy a new horn they are usually pretty cheap, get the high note lownote ones or the big CHOOOGA CHOOGA , those piss people off so i like them more

posted by  BanffAutoSpa_ap

Your Message