Does the cigarette lighter in BMW 3 Series remain powered after turning off the engine?

[SanIan]

Generally, the cigarette lighter in BMW 3 Series will power off 5 minutes after the engine is turned off. Safety shutdown situation: For most vehicles when the ignition switch is in the safety shutdown position, without circuit modification, it's impossible to maintain power supply after engine shutdown through vehicle settings. Determination by model: Whether the cigarette lighter remains powered after engine shutdown depends on the vehicle model. Some models cut power to the cigarette lighter immediately after shutdown, while others maintain power supply as it's a constant power source. Impact of remaining powered after shutdown: If power remains after shutdown, it continues to consume electricity, which may lead to battery depletion. If electrical devices aren't unplugged after shutdown and the vehicle remains unused for extended periods, battery depletion is certain. Introduction to constant power source: A constant power source means it remains powered regardless of engine status, without any switch for manual power cutoff. If power cuts off after shutdown, no electricity will be consumed, thus preventing battery depletion from this cause.