What is this part? It came with the car when I bought it new.
I know that is has something to do with the alarm system.
Does anyone know where I can purchase this part cheap or
only the Nissan dealer has this part? It has this number
on the case: PRO 9094C
This part still works. I removed it since the green wire
seems like it has broken off. There are three wires that
comes out of it...red, black, and green. Do I need to
connect the green wire? I can't remember if the green wire
was ever connected?

http://images.cardomain.com/installs...960_1_full.jpg

 

Link is bad...

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The requested URL /install...7960_1_full.jpg was not found on this server.

 

sorry.
the link has been fixed.

 

Looks to me like a aftermarket alarm shock sensor.

 

It's an aftermarket shock sensor for sure. It's been almost 10 years since I installed an alarm and I can't remember squat about the shock sensor wiring. I think all of the wires lead to the alarm brain, right?

 

Yes it's an old style shock sensor... $5
Red = power
Black = ground
Green (usually now Blue) = trigger to alarm brain.

You can buy a newer one that mounts inside the cabin for about $15.

 

but how come when i removed it, the entire alarm
system does not work anymore? the system doesn't
arm and there's no siren sound?
where can i get an exact replacement? anyone online
sites or any local nyc stores?
thanks

 

Any car stereo shop will be able to sell them to you for $10-$15. You don't need an exact replacement.