This bulletin applies to all 2017-2025 Audi vehicles. The coolant warning light may appear on the instrument cluster. Visually check the coolant expansion tank level, which should be between the minimum and maximum marks.
Due to the large coolant circuit capacity, there is significant fluctuation in the coolant level when the coolant cools down and heats up. If the coolant circuit is incorrectly filled or bled, this can lead to sporadic illumination of the low coolant level warning light.
Capture a photo of the coolant level first. Upload the photo to Doc-it.
The coolant level in the expansion tank must be set/checked according to the Elsa repair manual while the engine is cold.
The connector, including pins and contacts, should be checked carefully.
The contact surface of the pins and connector must be free of dirt and must not be damaged.
After unplugging and plugging the connector back in, perform a key cycle and check if the concern returns. If it does, continue with normal diagnosis.
Mike Mavrigian has written thousands of automotive technical magazine articles involving a variety ofspecialties, from engine building to wheel alignment, and has authored more than a dozen books that crisscross the automotive spectrum. Mike operates Birchwood Automotive, an Ohio shop that builds custom engines and performs vintage vehicle restorations. The shop also features a professional photo studio to document projects and to create images for articles and books.
