Alarm horn stopped working

I believe the horn stopped working by itself. I don’t know when since I haven’t paid too much attention, but do like its function when locking the car. When I lock or unlock the car and when you press the panic button, the horn does not sound, but the lights do flash for locking and the panic button. I have enabled and disabled it in VAG-COM several times and it shows on, but nothing works. The horn by itself, when pressed, works fine also. Any suggestions?

Interesting...
I have a 2003 Golf TDI with about 15K miles on it. Last week I noticed that when I locked the car with the keyfob all of the doors locked but the horn didn't honk. Annoyed, I tried unlocking and locking and again..no honk. So I unlocked, checked all of the doors and hatch and re-locked. Again..nothing. So I went into my house. About 5 minutes later I hear the horn honk For the next 4 or 5 times it worked fine and then it did it again. This has now happened three times.

I also noticed the other day after driving for about 1 hour that my doors didn't lock automatically at 10 mph. Related?

So.. I'm perplexed as well.

Sorry that I don't have any answers for you. I'll stay tuned if anybody has a solution.

make sure your hood and your trunk are completely closed, thats what got my locked honk back.

NB

Also verify the two 15A fuses on top of the relay block (where relay 109 lives) are good. Check the left one first.

Where is the infamous 109 relay located exactly? I've never played with it. I will check the fuses tonight if I can find out where it is.

Found the 2 fuses and the 109. I have the old black 109, guess I will pickup a new one. Should I just ask the dealer for a "109" relay? Also, the 15A fuse on the right(toward the passenger side) was blown and the one one the left was fine. Mine had tape over them making them hard to locate/see. What do the fuses do, what would make it blow, and would the 109 cause the alarm not to work? Any more suggestions since the fuse replacement didnt fix the problem? Thanks for helping me.

I didnt check the left one first, any deal? Why the left first?

Have you had any work done to the dash or had problems with your stereo? I had this probelm when I replace a warped part of my dash. The horn would not honk, but the doors would lock. The best part is that you could do anything that you wanted to the car and the ararm would not sound. But, the solution was that my radio was not pushed in all the way. Try that! Also, check to make sure your hood is latched.

Relay 109 is unrelated. Ask for the relay by part number (shown in that other thread).

I don't know when your car was made so I took a stab at suggesting the left fuse first. They reversed the functions of the fuses later. One is documented for power to flash the lights, the other is documented for power for the alarm horn.

If the replacement fuse didn't blow, then maybe the horn itself has died and took the original fuse with it. The horn is located up with the wiper linkage.

I pulled the horn today and tested it with 12V. Sounds fine. I put a voltmeter on the connector and it reads 12.3 volts, but not enough to run the test light. It must be a superficial reading on a sensitive meter. I hit the alarm and the test light did not come on or flash and the voltage on the meter did not change or fluctuate. If the horn is good and the fuse above the 109 is good, what could it be?

This has also happened to me a couple of times in the past. (2003 Golf) It has been fine for several months. Doors would lock but no honk. Like NussWag, sorry no answers but it's nice to know you're not the only one. Good Luck.

That just happened to me yesterday, too. I will have to look into it tomorrow. I did check to see if the alarm goes off when the door is opened while locked, and it DOES.

UHF, since you've got a 99.5 Jetta...

Got power windows and VAG-COM? Follow this procedure.

Select the "46 - Cent. Conv" controller, then "Meas. Blocks - 08" and make note of groups 003, 006, 007, 008, and 011. Report findings.

Got non-power windows and VAG-COM? Follow this procedure:

Select "35 - Cent. Locks" controller, then "Meas. Blocks - 08" and make note of groups 001, 002, 003, 004, and 007. Report findings.

block 3: Driver door switch
Box 1: DD key Sw
Not Oper.
Box 2: DD latch
Door open reads 11 / door closed reads 01

Box 3: DD latch feedback
unlocked or locked depends if door is locked or not
Box 4: dd C/L feedback
Safe (dosent change when open/closed or lock/unlocked)

Block 6 works the same as 003

block 010: signals
box 1: S. Contact : activated
box 2: truck lock: Not Oper : I cannt chage the status
box 3: T15 on/off : Term 15 on : Cannot change either

Block 11: Signals
box 1: Hood Radio Sw: Closed
box 2: Truck latch sw: Open or closed depending on if its open or closed.
box 3: sunroof sync:yes

Block 012: Central convenience module
box 1: Trunk remote: Not Oper or trunk remote when sw activated
box 2: Thermo protect ds/ps/rl/rr: 11 11 1

Block 15: alarm sounces
box 1: last: 4
box 2: 2nd: 8
box 3: 3rd: 9
box 4: 4th: 128

Says see label file in block 015

OK WHAT A RETARD I AM. Here is the story.........I went out to get more measuring blocks…..Scooby Doo fade out…..
When I purchased my car a couple months ago the remote didn’t work more than 8 feet away. Service bulletin said some were missing the antenna in the car. According to the schematics, the antenna has two wires, which come, out of the control box. I only found one. I went to the dealer and picked up the missing antenna wire. It came with two pins. I pulled the one from the box and installed the two with the antenna.
Now known to me, that is when the problems started. The antenna only worked from about 10 feet away, pretty much useless. Now onto the current problem, the alarm horn. While getting the measuring blocks you asked for I thought I would check the fuse above the 109 again. So I pulled the wire plug containing the antenna to easily check the fuse with it out of the way. I noted small numbers on the side of the plug. A quick check on the service bulletin showed it in pin 7 and 10. I saw the numbers and did a quick count and found the antenna in 9 and 12. Straight across the 7/10 in the symmetrical block. I put the antenna in the wrong spot a month ago or so. AND... Guess what the wire I pulled to fit the 2-antenna pin in was? Yeper, the alarm horn wire! Put the antenna in correctly and put back the wire I pulled and the alarm horn works and the remote works from down the street now! What an Idiot. I've spent countless hours and days trouble shooting both! AAAAAAaaaaa.