Effect of disconnection or total discharge of the battery on electrical systems in the vehicle, subsequent measures

WARNING: This page does not describe the selected car, but rather 7 other vehicles, including the 2005 Porsche 911, 2004 Porsche 911, 2003 Porsche 911, 2002 Porsche 911, and 2001 Porsche 911. However, it is still accessible from the selected car via links, so may be relevant.

Never disconnect battery with engine running!
Never start engine without securely connected battery!
Do not use a boost charger to start the engine!
Whenever possible, use jump leads with overvoltage protection!
Always disconnect both battery terminals before carrying out welding work on the vehicle!
Wiring harness plugs of control modules or other electronic components must be connected or disconnected with the ignition off. Exception: vehicles with the additional equipment M 536 (alarm siren with tilt sensor)!
NOTE: Concerning the M 536:
In order to avoid triggering the alarm siren (installed on right next to the battery) of vehicles with M 536, the battery must be disconnected with the ignition on (all loads must be switched off beforehand).