Hi.Sorry for the long post,but here goes.
Before I got my Supra from Rash he had a problem with the standard alarm when starting after having the car stood for a while.He then had an auto techie disconnect the alarm/immobiliser as he couldn't start the car before.Everything worked fine after.I left the car in the garage for about3 and a half weeks and when I tried to start it the alarm went off ,but then just stopped on its own as soon as the engine was running.This only happened on another occasion a couple of minutes later after I switched the engine off and started it again.I thought it might be the battery ,but what baffles me is that the siren is completely removed from the car,but still the alarm sounds.Today I replaced the battery with an Exide Maxxima DC900 and the alrm sounded when I connected it,but only for a few seconds.Has anyone experienced this before??