jbl

My Forester import had a Scorpion 1254/2454 Immobiliser fitted back in 2002 after import. Just recently it has not been 100% reliable in that it will not always disarm and allow the car to start. I have to try 6-7-8 times sometimes before it seems to switch off and let the ignition work.
I have two transponder units, the tiny tube like things, but neither is better than the other in reacting with the immobiliser. I don't think that they have batteries in them as they appear to be sealed and are quite tiny.
I suppose that there could be a poor connection somewhere on the main unit or electrical corrosion of some sort on a terminal but I don't know where on the car the immobiliser was fitted or even what it looks like. I tried a google search but nothing for a 1254/2454 unit.
I can contact the makers and see if they have any local installers who can check it out, original installers no longer exist.
Thought I would ask on here first to see if there is anything I have missed or for any further suggestions.

Cheers and thanks

JBL