Determining which source has possibly triggered the anti-theft alarm
WARNING: This page does not describe the selected car, but rather 26 other vehicles, including the 2009 Volkswagen Jetta, 2008 Volkswagen Jetta, 2007 Volkswagen Jetta, 2006 Volkswagen Golf, and 2006 Volkswagen GTI. However, it is still accessible from the selected car via links, so may be relevant.
The breakdown of the display content illustrated in Break down of display content for display group number 015 for display group number 15 for vehicles through 05.01, and Break down of display content for display group number 016 display group number 16 for vehicles from 06.01 on gives information as to which component triggered the alarm system last, and can therefore help the troubleshooting/repair.
This "DTC memory" cannot be erased.