Audi Filler Cap on Coolant Can Fool You
This bulletin applies to all 2012-2021 Audi models. The customer may note that the warning light is on with low coolant level or a coolant leak is found under the vehicle front.
The pressure relief valve in the filler cap of the cooling system can give the impression that the valve malfunctions. Coolant marks around the filler cap or the coolant expansion tank do not necessarily indicate that the cap is malfunctioning. Check the filler cap, according to Elsa. If the filler cap passes the test, do not replace the cap. Continue fault finding.
About the Author
Information courtesy of Mitchell 1
Information for Technical Service Bulletins comes from ProDemand, Mitchell 1's auto repair information software for domestic and import vehicles. Headquartered in San Diego, Mitchell 1 has provided quality repair information solutions to the automotive industry since 1918.
Mike Mavrigian
Motor Age Editor
Mike Mavrigian has written thousands of automotive technical magazine articles involving a variety of specialties, 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.