Audi / Volkswagen Coolant Reservoir / Tank / Bottle 5WA121407G

The coolant reservoir, also referred to as the coolant tank or coolant bottle, is an essential component located in the engine bay of vehicles such as the Audi Q3, A3, and TT, as well as the Volkswagen Tiguan and GTI. This factory-original OEM part, with part numbers 5WA121407F, 5WA121407D, and 5WA121407C, plays a critical role in the vehicle's cooling system by storing and maintaining a reservoir of coolant to regulate engine temperature. Common failures include cracks, leaks, or damages resulting in overheating, making replacement necessary to ensure proper engine function. Compatible makes include Audi and Volkswagen for models produced between 2016 and 2024, ensuring a reliable fit and performance.