Hey I installed a crimeguard 745i3 alarm in my Eclipse and recently a friend of mine gave me an extra siren. I tried wiring the siren directly with the one I already had and just grounding it but it wont chirp like its supposed to. Now tneither siren works until the alarm is triggered. I was thinking that I may need a relay to help power the second siren but does anyone know how to wire two or more sirens to an alram? Thanks in advance.

Well you need to know what kind of trigger your alarm is, or what polarity the alarm is putting out to the siren. Most alarm systems use a positive wire that goes to the siren, and then just ground the neg wire of the siren, but some alarm systems use a neg wire that comes from the alarm. To be safe when using 2 sirens with an alarm, you should use a relay. Get any 12volt SPDT relay. Assuming you have a positive signal coming from the alarm system: Pin #85 on relay-hook up to the positive 12v siren signal from the alarm. Pin# 86-hook this to ground. Pin# 87-hook up to battery or any high current 12 volt constant source. Pin# 30-hook this up to the pos lead of the siren, and just ground the siren's neg to ground. hope this helps, any more q's, just speak up