For a 1999 infiniti g20 what causes the alarm to go off?
It seems that the alarm will go off if a door that was locked is opened and the key hasn't been in the ignition or used to unlock the door for a while.
Contrary to popular imagination, it is not the Sentra. The G20 is a completely different car. Overseas, where there is no made-up "Infiniti" brand, it is the venerable Nissan "Primera". The 1991-1996 models are the "HP10" chassis, the re-introduced 1999-2001 is the "HP11". It is still sold in the latest HP12 iteration like in Japan and the UK.