connections for a pulsed horn output

Hey Folks I have a small problem with my car alarm. I wanna add the factory horn with the alarm siern. I have a constant output from the brain to run the siern but, I need to have a pulsed output for the horn, so, it won't burn up. I've looked at the relay section on the webpage and when i use the 12 volt flasher for the pulsed output, all I get is a constant horn. The horn needs a negative input for it to operate(Ford Mustang). This is how I have it set up using two relays. 86 connected to + siern output from brain 85 connected to ground 87 connected to 12V+ 30 connected to X on flasher using another relay to change polarity, I have comming from the L on the flasher to 86, 85 and 30 are connected to ground and 87 connected to the horn which is a negative input. This did not work and gave a constant horn output so, I moved the flasher in between the 87 and horn connection on the last relay and, it still gave a constant output. Any help would be appreciated. Thanks Aaron

This is the diagram that I used to do exactly what you're trying to accomplish...except replace that light with your horn in the diagram. I think the only difference I had from that diagram (which you'll probably have to do, too) is I put pin 87 to ground instead of 12v+...this is because my horn needed a negative signal to work. Write back with your results. Good luck!

Do I still need to add a diode in line with the alarm so it doesn't fry the brain of the alarm. If so, would I install it in between pin 86 and the brain module. thanks Aaron

I didn't use one...I don't think you need to. You're only working with the siren's wire....not any sensor wires or anything that will be sent back into the alarm (that's if you hook it up correctly )

cpgoose, Thanks for the help. I will try your suggesetion tonight when I get home from work. I will post an update soon. Thanks Aaron

cpgoose, I removed one of the relays I was using and I connected everything how it is shown in the above diagram Except I changed the 87 pin to ground. This still did not work. I double checked everything and when the alarm goes off, it is still a constant horn blast. The website (the12volt) says my horn wire is a yellow(-). I took the sterring column apart and I connected the output for the alarm to a different color wire. This wire, when connected had the horn honk so, I figured it was the right one. Could this be the problem? Also, I hooked the flasher up to a light and it worked so, I know it is good. I think everything is connected right but maybe I have found the wrong wire in the steering column. What do you think? Thanks Aaron

Hmmmm, what year is your car? What type of alarm do you have? Maybe there's something different about the signal the siren is working on. Do you know if it's outputting a positive signal to work the siren?

cpgoose The alarm is a Omega K-9 Classic. The siren output for the alarm is Positive. The car is a 94 ford mustang. I took and extra relay that I had a connected it as shown above to a light, and it worked properly. So, I know, I know how to hook it up correctly. But, when this is added on the car, all the horn will do is a constant blow. The alarm is set for a constant output for the siern also. Could I have the wire coming from the flasher hooked up to the wrong wire coming from the horn? I have no clue. If all else fails, I guess I could run a wire from the flasher up to the horn in the engine compartment. I dont know. What do u think? Thanks Aaron

Ok, I'm going to ramble a bit to see if we can figure this out: 1. When you connected the extra relay to a light, and you said it works....are you saying you hooked up a relay and a flasher to your alarm and to a light, and the light actually flashed? 2. Since your horn is constantly blowing...I guess you have found the correct wire....so going to the horn's wire in the engine compartment will only be the same thing. Hmmm....on the 12volt's site, it says the horn is a yellow(-) wire. I also checked on bulldog's website, and that says you have a yellow/light green (-) wire, and designtech's website says the same thing. Maybe that could be it...do you see any yellow/light green wires down there? 3. If you do in fact have the correct wire, it sounds like it has to be the wiring of the flasher. Are you using a 12v flasher with 2 posts on it? Do you have the X and L hooked up correctly?.....with X going to the relay, and L going to the horn's wire? 4. Are you sure you tapped the positive wire of the alarm's siren with pin 86 of the relay? I tapped the siren's red wire in my car...not the alarm's brown wire that goes to it. That probably doesn't make a difference, but just showing you what I did. 5. Here's a post from when I helped someone with this before. It basically just says everything you and I have been saying. I was just reading it to make sure everything was the same. In there, it says that (for my car), my horn shows (-) in the diagram (just like yours does). But when I tested it, it rested at ground. So I guess what the (-) means is that it needs (-) to sound. But I think you're doing this all correctly because your horn is actually sounding...its just not "flashing". Hmmm... 6. When the alarm sounds (by the way, how are you testing this....are you hitting PANIC?)....does the flasher at least click? Can you feel it trying to work if you hold on to it?

Cpgoose, To answer your questions #1 I hooked the relay to an extra car battery outside of the car and this worked. #2 I havent looked yet because I removed the air bag and found a purple wire that showed ground when connected. I will look tonight when I get home from work. #3 Using a two post flasher. I tried the flasher both ways still with a constant horn blow #4 The brown wire is connectd to pin 86 #5 yes this #6 I am hitting the panic button to set it off. The flasher when I hold it in my hand is not ticking or clicking. Does this Help? Thanks Aaron