I have a '02 impreza wrx and am trying to program another alarm remote into the system. I have followed the instructions in the owners manual where you unlock the car, sit in the drivers seat and close the door, insert the key into the ignition and cycle it from lock to on 10 times in 15 second. This is were the horn is suppose to honk to let you know that the car is in program mode but I can't get it to do this.

I have tried a ton of times and can't get it to work, any help would be appreciated, Thanks