2000 expedition horn won't work

Check for blown fusible link that supplies switch.

There was a recall done on those vehicles in 2008 for the same issues. Something about a clock spring. If the recall work has not been done on your SUV, bring it to a dealer.

https://s26.postimg.org/e04ja62e1/horn.jpg

Click on the link.
As you can see, no actual horn relay, but, there is the security module. As far as the security module location, seen two different locations in my database, so I'm not sure of location?
Give me a second, will try to post wiring diagram.

You probably have a bad ground in the electronic instrument cluster, or cluster connection to wiring harness. I would recomend you have a qualified auto tech diagnose it. It is not a easy fix.

you should be able to disconnect the horn at the horns themselves just follow the noise to find the horns be advised that horns are required to pass safety inspection

Normally there is a horn relay, try replacing that. The contacts can weld together and keep the horn on. If you take the relay out and leave it out, you won't have a horn but at least it won't be blowing all the time.

it might be the fuel pump take the output hose off of it and crank the engine and see if fuel comes out of the pump if it does the fuel pump is not the probelem. if it doesnt come out or if it slowly comes out than you need a new fuel pump

YOUR HORN MOUNTED BEHIND THE RADIATOR GRILLE.WHEN YOU REMOVE HORN HOT WIRE IT.IF HORN WORKS PROBLEM IS IN THE HORN RELAY OR HORN BUTTONS OPEN.IF HORN DONT WORK WHEN HOT WIRED IF FAULTY.

There is the actual horn located in front of the radiator on the support.
I would also check the horn relay. You want to make sure that when depressing the horn button you are getting 12 volts to the horn, but it needs to go to the relay first.
I have a diagram for you :


2000 Ford Expedition Horn Relay Location
Please let me know how it goes.

clean multi function switch with electric contact spray. get spray at radio shack. multifunction switch is on the bottom of the direction indicator arm. spray liberally