Hi, I'm I need of some help, I have a 2002 forester sport, can anybody tell me where the alarm unit is located as I think I need to change (if possible) the main battery unit for it, I've checked in the engine bay and I'm really struggling to find it. I believe it a sigma alarm (factory fitted)

Many thanks in advance.

 

back up battery is in the siren, the ecu is behind the glovebox but theres no battery in it