Volkswagen Tiguan persistent parasitic battery drain issue with unresolved diagnosis on Volkswagen Tiguan

Some Volkswagen Tiguan owners report experiencing persistent parasitic battery drain issues, which can lead to frustrating battery depletion even when the vehicle is turned off. This problem often stems from malfunctioning components, such as interior lights or faulty systems that continue to draw power. Symptoms may include the battery draining to 50% overnight, frequent jump starts, or wet floors due to blocked drain channels on the sunroof. To diagnose the issue, owners can use a multimeter to test for current draw and ensure the battery itself is functioning properly. Additionally, some owners find that a failing battery or faulty Can module, which may require a software update, can contribute to these problems. It is crucial to address the root cause of the drain to prevent further battery issues and potential vehicle breakdowns.