Strange Alarm Horn Defective Code

[redline21]

I've got an alarm horn code that keeps popping up on my 2012 A7 and I can't figure out why. My alarm seems to work fine when I tested it by opening the door from the inside when locked and by running the VCDS test. I also get a chirp when locking the car. I clear the code but it comes back pretty much immediately. Does anyone have an idea as to what I should check next?

Address 46: Central Conv. Labels: 4H0-907-064-46.clb
Control Module Part Number: 4H0 907 064 BR HW: 4H0 907 064 BR
Component and/or Version: BCM2 2.0 H31 0333
Software Coding: 0126023A20FAF48580B00A8002010000000000000000000000 0000000000
Work Shop Code: WSC 02391 785 00200
VCID: 7AADFDD1ACDCCA6A617-802E
1 Fault Found:

01134 - Alarm Horn (H12)
014 - Defective
Freeze Frame:
Fault Status: 01101110
Fault Priority: 2
Fault Frequency: 1
Reset counter: 180
Mileage: 127650 km
Time Indication: 0
Date: 2024.04.25
Time: 18:14:45

[RAF_S7]

The horn assembly has a nicad battery pack inside, and early model cars were susceptible to corrosion inside the horn. Given the age of the car it’s possible that this is what your experiencing.

It’s an easy exchange of the unit (often come up on flee-bay) or you can try opening the horn assembly and changing the nicads.

[redline21]

Resolution update for anyone else looking in the future: I ended up purchasing a used unit online and swapped it out and that seems to have fixed it. I cleared the code and it hasn't come back. I'm guessing that a unit that is still capable of chirping/alarming may still cause an error code if it's internal battery starts to go and gives an abnormal voltage reading.

[Gunnarrrrr]

I would highly advise against just getting one on ebay and throwing it in, chances are it’s not far behind your current one. I’ve been through this many times, and the most recent time I grabbed 3 from a wrecking yard before getting one that didn’t have dead batteries or extensive acid leakage, all from 2008-2012 cars. I decided to pop open the first good one I could find, and order a pair of new genuine Varta 3.6v 140mah batteries. they apparently don’t make the vertical standing ones anymore, so instead of modifying them I just soldered wires to the old battery location on the board and taped them to the outside of the module.

Yes, it looks like a bomb. It’s not a bomb. This was for a B6, if it were a C7 I probably would’ve put in a little more effort. Bottom line is, these things typically last about 10 years tops, you might get 12 years if you’re lucky. If your module is more than 5 years old, pop it open before the batteries pop and destroy the board, and give it a fresh pair.




Sent from my iPhone using Audizine Forum