car alarm siren

My car had an alarm system installed in it before i bought it, and i have no information on its make or brand.

The system works fine, but the external siren mounted in the engine bay doesnt work. Ive turned the little key in the back of it, but still nothing.

The internal siren mounted in the cabin still works, and my indicator lights flash when the alarm is triggered.

The external siren under the bonnet has 4 wires going into it.

Black, Red, Orange and Green.

The Black is Earth.

Ive buggered around with it for the last hour and dont know what im doing!!!

I bought a new siren, with 2 wires coming outta it, Power and Earth.I cut the 4 wires going into my original broken siren and joined the Earths together.Now... the other 3 wires are RED, ORANGE and GREEN.If i connect the RED wire to Power the Siren goes off constantley.If i connect the ORANGE wire to Power the Alarm goes of.(Lights+Internal Siren inside cabin)If i connect the GREEN nothing happens.If i connect all three the Siren goes off constantley, and as soon as i remove them the Alarm goes off!!! LOL!!! BUGGER!!!Any help would be great, or its a trip to the local Sparky $$$$$

Thanks Matt

The original siren that was in your car is a battery backup siren,which is why it had a key.If you don't want to have another battery backup siren and just hook up a normal siren,you need to find out what kind of alarm you have,get the manual for it, then find the alarm brain,and find the wires for the siren.."ole blake"

you gott the ground right hook up the red wire form new siren to the green wire that was already there. arm teh system and disram the system see if the siren chirps or hit panic on alarm. tape off the other wires only goign to use 2 of them. red is a power wire that why the siren went off orange wire looks liek a trigger wire door, instant waht ever. green shoudl be the wire from the alarm siren output.

Ok, i gave up on the 2 wires alarm and went and bought a Black Widow siren with back-up battery inside. This siren has 4 wires comeing out of it, just like my old siren.

I have a Red, Blue, Grey and Black comeing out of it.

But no matter how i wire it up, as soon as i turn the key in the back of the siren it just goes off constantley!!!

If i wire it up correctley should the siren be quiet no matter the position of the key in the back of it, until the alarm is triggered?

I took my old siren apart and one of the 3 little 6volts batteries is toast which is why i think it doesnt work.

Inside the old siren the wires connected to the circuit board, and each wire had a name printed where it connected.

Red wire went to "R"

Black wire to 'G/SW"Orange wire to "T6-"Green wire to "T6+"

Ive just opened up my new siren and found where its 4 wires connect to.

Green "8"

Black "0" (with a cross thru it)Orange "2"Blue "R1" "6"

Any help would be great. Im trying to avoid an expensive trip to the auto electrician...

Cheers.

All of the wires should match up..try this.Make sure your alarm is in valet mode.Hook up all the wires.Leave the key in the off position.Close all your zones.(Doors,hood,everything.)Take your alarm out of valet mode,and arm the system.See if it chirps when you arm and disarm.If it does,then disarm your alarm and turn the key to the on position,and see what happens.If it starts to go off,then try arm and disarming your system to see if that makes it stop.If it does then your good.If it doesn't the the siren is sensing that it is not receiving power and going off.."ole blake"