Horn & Alarm Wiring
 

i kinda need somebody whos pretty electrical friendly...i have an alarm with a siren thats an aftermarket part. its currently hooked up but only came with the hot the fuse and the ground with the siren. so theres no door shock or keyless entry...its just a str8 alarm...well what i want to do is wire the factory horn to the aftermarket siren. some say id need a relay but im not exactly sure why...there wouldnt be a keyless entry...it would only be an alarm....so is this possible?

second problem is do you know where the factory alarm is?...because i still have it hooked up but i just cut the wires to keep it from going off 24/7 and draining my battery..thing is i had someone else cut it and it was back in 07 so i surely dont know where any of the components are...anyone know where they are

Factory alarm if it has one is a module located on the driverside underdash panel its also the keyless entry module. Yes you would need a relay to trigger the horn becuase most alarms are (+) triggered output for a siren and you would need to switch it to a (-) trigger for the horn. The horn wire can be found in the steering column and its a lt. green/blue and is (-) triggered, but just double check with a meter.

well since i still have the factory alarm....doesnt that mean that my relay is still technically hooked up??...cudnt i just use it? disconnect the relay and wire it in the circuit with the aftermarket alarm and factory horn?...and will i plain as day see the module or will it be kinda hidden? and will i need to get into the steering column and get the horn wire just to wire it all together? or shoudnt there be a wire somewhere around the horn leading to the switch in the steering column?

Ok I didn't even read your reply but it seems you don't get it. The aftermarket alarm has a ground trigger, but your horn is already directly connected to ground. When you press your horn it is connected to positive. So you would need a relay that is activated by the ground trigger from the aftermarket alarm, to give a positive signal to the horn turning it on.

EDIT: In essence if you just connect your horn to the alarms output nothing will happen, since the alarm will be grounding what is connected to the output, and the horn needs power not a ground.

ok i understand that but what im saying is....cudnt i use the factory relay? seeing as how when i got my factory alarm disconnected all they did was snip a wire...so technically everything should be hooked up...thats why im askin cudnt i just use the factory relay from the factory alarm to finish the setup? and i already understand what you said toofatt as far as needing a relay becuase of the diff trigger outputs but thanx for simplifying it even more....