Search blower motor resister. They go bad and drain your battery 100%. They look like a porcupine....I'm sure other guys can tell you the part number and how to test it.

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2002 X5 4.4i Sport Wheels
2014 X5 35i M Appearance & suspension package
1995 Porsche 993
1972 Porsche 914-6
2020 GLE 450 Twin Turbo
2019 Alfa Stelvio 500hp Quadrifogilo
Many motorcycles