Horn and Cruise Control Not Working

[jevchance]

Hey all,

I have a 2000 Mercury Mountaineer. The horn and cruise control are not working. At first I suspected the clock spring, but the horn doesn't work when I arm my factory alarm, or hit the panic button on the remote.

Could this still be the clock spring? I would expect the horn would still work with the alarm if the steering wheel connector were broken.

I have checked all my fuses.

I also have removed my horns, checked the connection, and cleaned the connections and reassembled. I was told a bad ground at the horns could cause this.

I'm at a loss. Any suggestions before I start tracing wires?

 

[Dono]

You sure fuse 9 at your drivers door is good? Seating properly? I'll look for that schematic I was using troubleshooting my cruise control. I doubt it's the clock spring.

 

[vroomzoomboom]

what dono said. there also is a fuse under the hood in the power distribution box that some people overlook (and i have blown about 5 times now).

 

[jevchance]

I checked the fuses at the fuse box and under the hood.

That being said, you know how fuses can be. I visually inspected them but did not test them.

I think I will go ahead and replace Fuse 9 regardless of what it looks like. Thanks for the tip.

 

[Maniak]

Could this still be the clock spring? I would expect the horn would still work with the alarm if the steering wheel connector were broken.

Time to break out the wiring diagram.

For example. I had no dash blinker for my left turn signal. I would have expected that to work no matter what. I was checking fuses/wires all over the place and then tested the multi function switch. It was all good.. While testing the multi function switch I found my wiring diagram.. I followed the wires and found the dash indicator would stop working if the wire to the front bulb was bad.. I checked and viola.. found the bad part...

What I'm getting at is sometimes they wire things in ways where a break in 1 place will take out something you wouldn't expect...

~Mark

 

[Dono]

schematic:
http://search.ebscohost.com/
ID: rrcc
PW: rebsco

check both the cruise control diagram, and the horn diagram.

Double check fuse 10.
Look for 12v at the yellow/Lt green trace wire at the steering wheel (air bag removed).
If you have 12v there, try switching your meter to ohms, and stick 1 lead on the yellow/lt green trace wire again, and the other at the black/white trace wire. This should show high impedance, then when you push the horn the impedance should drop. This checks your horn cct, not cruise.

Im betting that you don't have voltage at the yellow/light green trace wire in the steering wheel.

After confirming no voltage on the yellow/light green trace wire you will need to follow the voltage along the wire.

1. Check fuse 10
2. Try swapping the horn relay out with another relay (Im hoping its the same as the other relays).

Strange on the yellow/light green wire though. It also has the anti theft module on it. If it had no voltage, I don't think your truck would start.

 

[jevchance]

Thanks Dono for the specifics, and the link.

Also thanks everyone for your input. I'll work on it a bit tonight and post progress tomorrow.

 

[jevchance]

Well, fuse #10 under the hood it was!

I must suck at checking fuses.

Thank you everyone for your input. You helped this guy out today!

 

[Dono]

delux!

love an easy fix. Congratulations.

 

[jevchance]

Thanks very much for your advice Dono!