Electrical Problem: Lost horn and key/headlight on warning chimes

Mustang5L5

That is…until I whipped out my Bissell

Mod Dude

Feb 18, 2001

43,235

17,920

224

Massachusetts

Feb 24, 2006

#1

• Feb 24, 2006

• #1

At 30K miles i had my first gremlin. I lost the horn as well as the key in/headlight on warning chimes.

I did notice that right before I lost the horn it sounded weak and broken. Afterwards nothing at all. Next day i noticed the chimes were not working.

Car is still under warranty but i don't want to lose time/money in bringing it in if i can solve it in an hour or so of work.

First things first, i don't have a manual so where is the fuse for the horn?

Secondly, what would these things have in common to cause them to go out at the same time??

If anyone has any wiring diagrams for a 2003 that would help.

 

N

n0v8or

10 Year Member

Aug 23, 2003

604

8

39

Rhode Island

Feb 24, 2006

#2

• Feb 24, 2006

• #2

I have the '03 manuals, and I don't see anything common that would kill both the horn and headlamp warning chime. Do you have an aftermarket alarm installed?

The horn fuse is a 20A mini-fuse located in the fuse/relay box near the battery. Open the hood, Standing by the front left tire, push in the tab nearest the engine and lift the cover. The first 4 fuses (top to bottom) in the left column should be 20A - 20A - 30A - 20A. The second one from the top is the horn fuse.

 

Mustang5L5

That is…until I whipped out my Bissell

Mod Dude

Feb 18, 2001

43,235

17,920

224

Massachusetts

Feb 24, 2006

#3

• Feb 24, 2006

• #3

Nope, my car is pretty much stock. No alarms.

It went out while driving during a rainstorm. I just happened to notice the chimes not working as well.

Horn switch "clicks" like normal and when i hit the lock button twice the horn no longer beeps but the parking lamps flash

 

Mustang5L5

That is…until I whipped out my Bissell

Mod Dude

Feb 18, 2001

43,235

17,920

224

Massachusetts

Feb 24, 2006

#4

• Feb 24, 2006

• #4

You gott be kidding me.

Went outside to check the fuse and now the horn and warning chimes work fine! What gives!

Something must be shorting. Anyone know what these would share to cause such a thing?

 

N

n0v8or

10 Year Member

Aug 23, 2003

604

8

39

Rhode Island

Feb 24, 2006

#5

• Feb 24, 2006

• #5

The weak horn before it died suggests a bad horn relay.
There is a plastic relay box right behind the fuse box under the dash. It has 4 relays in it. The 2 relays farthest from the fuse box (therefore closest to the engine) are the horn relay and trunk release relay. You could try swapping them (I think they are identical) and see if the problem moves. Sometimes just removing and re-seating a relay fixes it.

 

Mike97gt

it doe snot

Founding Member

Jan 26, 1999

10,633

7

89

the people's republic of massachusetts

Feb 24, 2006

#6

• Feb 24, 2006

• #6

i just noticed this thread. keep us posted if it comes back. just bump it to the top with the details.