Check your alternator output---voltage should be no more than approx. 14V. Mark

How do you do this? Are there steps anywhere on the site?

Hints to having an overcharging battery are: excessive water usage, and, especially right after you turn off the engine, you can hear the battery fizzing (like a coke can after you open it).

Put a volt meter on the battery while it's running - If you are getting something really high, then you know your answer right off the bat.

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It is a truism that almost any sect, cult, or religion will legislate its creed into law if it acquires the political power to do so. Robert A. Heinlein


09 Jetta TDI
1985 300D

Does anyone know if the fans that cool the engine are powered by the battery? I've noticed my 2 fans up in the grill are out, and thought it might be inter-connected.