Audi newer cars are very particular about how we jump or charge the battery, if we don’t do it correctly, it may damage the Power Management System or Battery Management System or even ECU and other expensive Electronic Components. Most Audi Batteries are in the trunk on newer cars, therefore they always have positive and negative poles in the engine bay.
Charging or jumping the battery: I left the for 1 days and the battery went down to 9V. The key fobs don’t open/close doors, nothing. The battery is located under the spare tire, there are positive and negative poles in the engine bay, so don’t charge or jump the battery from the battery itself, must use these 2 poles in the engine bay. The original battery is AGM so charge with the setting accordingly.