2000 XJ horn not working

2000 XJ no airbag light on, no cruise control to not work.
Horn relay clicks in fuse box, no 12v at wire where it plugs into horn. Need help!
Tried wrapping wire around the relay "blades" hoping to just run a wiring from the realy to the horn(butch) until I can fix it the right way. Going on vacation this week and really want a horn.
Found 12v to the relay(test light lit up). Only other teriminal that showed 12v, showed it all the time also and did NOT show 12v when the hron button was pressed. Seems backwards to me.
Help?
Worst case scenerio I will wire up a cheapo HF airhorn with a button but when you need a horn "right away" it sucks pressing a button thats not where you are used to pressing one.

I did a search and went through the 8 pages but didn't find help. Anybody know what color wire coming out of the fuse block goes to the horn?

I don't know the 2000xj wiring but here is a link to automotive relay wiring.
http://www.classictruckshop.com/clubs/earlyburbs/projects/bosch/relay.htm
You should have 12v at pin 30 from fuse box
87a pin not used >will read 12v when relay is not energized
87 to horn >will read 12v when energized
85/ 86 is power to the coil which energizes and pulls contacts from 87a to 87 one will be 12v and other will be ground

you could pull the relay out and put a jumper wire into 30 and 87 and it will give you power to horn to see if horn is functional and wiring is good to horn.

I'm not sure if the horn button sends power to the relay or is a ground when pressed in this application. If you clip your test light to power and probe wiring at 85/86 and it lights that would indicate to me that there should be a power signal from horn button to activate the relay. Them clip you test light to ground and the opposite wire 85/85 should be the signal when horn button depressed.

hope this help

Do the jumper like chasdb says to see if the horn itself & related wiring is actually working. If then horn doesn't work then, wire straight to it from the battery to see if it works.

How did you notice the problem? What work has been done to the XJ recently? Has there been any recent electrical work or any recent work that could've pinched any wires?

My '90 XJ did this and it was easier to just rewire everything related to the horn. But it sounds like you have addtional wiring problems.

If I tested it right(I think I did but it doesn't make sense to me).
85 had power(test light lit with relay out).
86 had power also (only when the relay was in)but test light went out when horn button was pressed.
I think I might wrap a wire around each relay terminal and test them all when the horn button is pressed in.

Looking at the bottom image on http://www.classictruckshop.com/clubs/earlyburbs/projects/bosch/relay.htm

it looks like 87 should be the terminal sending power to the horn(87a doesn't have anything in the fuse block)(starting to make sense to me now)

GF told me horn didn't work, I drove it the next day and it worked. Next time I drove it, it didn't work. No work was done to it recently that would have pinched a wire. Head was replaced in January, problem happened probably in April or May.
Gonna try what chasdb said, hopefully I'll get somewhere tomorrow after work. Thanks so far.

Do this the easy way: just swap in a good relay to test. Did you test the horn itself? Hook it up directly to a 12v source and tap on it with something to see if it is intermittent.

Remove relay and jumper the terminals across from each other and see what happens.

Pelican said:

Do this the easy way: just swap in a good relay to test. Did you test the horn itself? Hook it up directly to a 12v source and tap on it with something to see if it is intermittent.

Click to expand...

I swapped the relay with 2 others, same situation. Horn shouldn't be bad, it only 8 months old. I'm not getting 12V at the terminal at the horn.

check the owners manual for a fuse, might be one in the PDC since all of the wires are up there

ehall said:

check the owners manual for a fuse, might be one in the PDC since all of the wires are up there

Click to expand...

My owners manual says to look on the panel near the fuse box for fuse id. Yeah...there's nothing there.

If it's electrical and it suddenly stops working, always check the fuse first. Fuse 21 in the cabin box (7th fuse down, right column) on my 97, might be the same on your 00.

With all the steering wheel controls not working I personally would inspect the S.I.R. coil(clock spring). Does require removal of steering wheel.