Horn blows after I installed battery

check relay for dash lights. Fuses that blow sometimes destroy relays.

You need a new headlight switch most likely have the dealer confirm this before replacing any parts.

check for blowed fuse or bad relay, you can hook test light to see if horn getting power when you press horn pad if fuse and relay okay,remove horn and hot wire it if it blows, more likely horn pad with airbag in steering wheel bad,if horn pad bad you have to replace whole airbag with with horn pad as a unit.if horn dont blow when hot wired then horn it self is bad.

reset the alarm/immobiliser according to the book......(every time the battery is disconnected.)

I'd start by hooking 12 volts with a battery charger directly to the horn to see if it blows. then check if you have power to the positive connector when activating the horn button. Then if you dont, see if you have power to the horn relay, located in or near the fuse box

replace the horn relay;or the horn button on the steering wheel is grounded and energizing the horn. any maintenance involving the steering wheel can be dangerous becaus of the air bag. if you just want to stop the horn, remove the relay, probably located in the fuse box under the hood. check the manual for location, but if your state has a safety inspection it will need to be fixed before the inspection is due

there might be some corrosion on the plugs that hook onto your battery.

The very first thing you need to do is disconnect the 12 volt battery source, remove the positve lead as well as the negative lead to be absolutely sure, you must be careful, I would wear safety glasses as well cause anytime you work around batteries there is a possibility of spark and ignition that can cause the gasses produced by a battery to explode sending battery acid into the air and on ones self.

Next locate the alternator adjustment bolts , wire leads connecting to the alt. mark those necessary wires so that you will be able to install them back into their proper place on the new alt. remove alternator belt and note conditon, often this is the best time to replace it with a new one. once you have all bolts loose thne you can lift the alternator from it's rest , take careful note of any spacers used on the pivot mount side of the alternator as well as any wire leads connected you could not see from above. replace in opposite mannor as removal... hope this helps..

Should be under the dash with the rest of them. Its a black bos should be square or it could be in the engine bay near the battery or other type of electrical componets.