2001 BMW Z3 battery runs down after 3 weeks.

[cyclops222]

Son In Law car. Brand new battery. Do these cars have a lot of Parasitic Loads on them ?
Stuff still on after car is turned off ?
Like station memory of radio.

 

[arks]

They shouldn’t. I‘ve had a 2001 BMW 530i for 21 years and never had a parasitic drain. Does the Z3 have an underhood light- maybe the mercury switch went bad…. The other thing to consider would be the new battery- I had one a few years back that was bad from the factory; as a matter of fact, had the same symptoms as yours- they replaced it no problem.

 

[cyclops222]

Thank you arks. My thoughts exactly.

 

[Mc Tool]

Come on cyclops ....get your clamp meter out and measure the load on standby.

 

[cyclops222]

He is going to leave it alone. Realized that he had not used it for 4 weeks due to cold weather. Will run it every 2 weeks from now on. His call.