Help needed: Alarm not setting
 

I believe my car has a factory fit Sigma alarm on it (It's a 96 Impreza Turbo). The keypad that's fitted to my car will arm/disarm/lock/un-lock the doors, but whenever I use the remote to do the above it will not work! All I get is a little red light flashing at me (next to the button on the remote).....I have just changed the batteries in the remote for brand new ones but it's still doing it!

What on earth is wrong and how can I sort this out?

TIA

Is the alarm on the car getting power? check the cables & fuses to it.