can i accomplish this?

hi I want to modify my keyless entry system using relays. I don't know alot about relays so i'm not sure if i can do what i want by using them. the signals that are sent from my keyless module are less then 12 volts (i think they are around 5 volts). What i'm planning to do is use the signal from my panic button to open my trunk. when the panic button is pressed a signal is sent out to the horn. when the lock button is pressed twice a signal is sent to the horn and the lock module. what i wanted to do is use a relay as a switching device that would sent the 5 volt signal that would normally be sent to the horn to either be diverted to the horn in the case of the lock button being pressed or if the panic button was pressed i would like it to be diverted to my new trunk actuator relay. My quesiton is can i use the common SPDT relays even if i'm not using 12 volts in any of the relay setup? does anyone have a simple wiring diagram that would kind of give me an idea of what i'm looking for? I checked out all your relay diagrams and i can't see how i could use them if i'm not using a trigger that is not even 12 volts.

Yes you can... try it.. you can energize a relay with a regular small 9volt square battery..

I thought that the coil in the relay requires at least 12 volts to operate it..if my inputs are less then 12 volts (say 4 volts) I guess your saying that still will be able to pull the coil? anyone have any wiring diagrams which don't have a require a contstant 12volt source in the diagram? like i said all i need is for the relay to act as a switching device where if it gets a a pulse from two sources it sends one signal one way and if it gets a signal from only one source it send the signal to a different direction.