First off: great forum, learned tons of stuff by searching!!
1st Audi so take it easy if noobing.
model: 1999 a4 avant 1.8t (stock) but cant wait to mod-out!!
note: I've found tons of info an alarms and horns but need some questions answered. oh yeah, I do not have a vag-com.

So, I replaced my weak stock factory alarm w/ a 120db 12v siren. Before I changed out stock I pulled wires (1) blk/wht and (1) brown. I figured the blk is ground and other one is power. But I read in another post that it's the other way around. Then hooked stock back up just to make sure that it worked again after disconnecting it. It did but produced a weaker level. I then just hooked up new 120db siren and did a test; on lock it produced a weak level peep, when alarm sounds its no where close to what it produced at the audio garage. I also read in another post that the horn has it's own battery located in ( passenger rear panel ).

3 Q's:

1. Which wire is ground?
2. Which wire is power?
3. Should I replace horn battery?


Thanks!
astar

My exterior goal:





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[IMG]local://upfiles/23189/06608A41E79A4414AA5E1D4510D2B175.jpg[/IMG]

 

I did the same exact thing with equally disappointing results. I think somehow the power source isn't providing enough juice or maybe thats the way it was designed. The alarm was also my first attempted mod but I since then forgot about it. Sorry I can't answer any of your questions, I also need more info on this problem.

 

Yeah, first minor mod also, thought i would get a loud alarm and a nice chirp when activated. Maybe the seperate battery for the alarm horn thought i heard about is not a 12v.

I need to hit up members; Jestnomen, avant80@2.6, PandaXpress and clconversion who I've learned so much info from. All these guys provide outstanding advice and tech support.

If you hear or find anything, please let me know. I will be checking this post daily.

Anyone else has a suggestion or idea would be great!

tanks,
-A

 

Yes your wires are correct. Brown is ground and blue is +12V. You can verify this with a test lamp or a multimeter.
However, since the stock siren was designed for use inside the trunk you need to mount the aftermarket siren under the body of the car inorder for you to hear it. Also you might run into the problem that your aftermarket siren may need a longer 12V+ pulse than the stock siren in order to hear it. In this case you would have to wire in a timed relay and program it to throw 12V+ for a specific time, long enough for the siren to fire as it did with the aftermarket alarm that you took it from.

Hope this helps.

Remember, try placing the siren outside of the car. In My 98 A6 I had the same problem. With the aftermarket siren in the trunk in place of the factory one, it was Quieter than the Stock Siren!!!

And as far as I know the backup battery for the alarm isn't connected to the siren.

 

thanks bro, i will look into this:

"longer 12V+ pulse than the stock siren in order to hear it. In this case you would have to wire in a timed relay and program it to throw 12V+ for a specific time, long enough for the siren to fire as it did with the aftermarket alarm that you took it from."

keep roll'in

-a

 

Thanks, houndz.

Can you provide me w/ a detailed DIY?

-A