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Old 12-14-2012, 11:12 AM
RufusKing RufusKing is offline
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Mein Auto: Z4 3.0i Roadster
Originally Posted by JavierBayArea View Post
This problem seems to be sort of random. I had the problem, took it to bmw and they replaced the electronics.

A few weeks later i saw the problem again, and then never again.

My best guess is that moisture shorts something out in the electronics. every time i've had this problem the entire front window fogged up right after starting the car.

Just next time this happens to you, check if it's early in the morning when you start the car.
Actually from everything i have read on this it seems software related. the issue is that these AC units are more like our radios and PCs now they have to properly be booted in order to be used. I suspect that the T-Fix above is energizing the brain before the button is pushed which is allowing the AC to initialize without any issue. Of course this is merely speculation but sounds like a logical reason based on what everyone posts on this issue. Unfortunately I havent had the issue to test the theory.

NOTE: i am not implying that the AC is a PC I am comparing the vehicle brain to a PC because that is where the initialization of the AC begnis.
This one is called OPey

2009 BMW Z4 sDrive 3.0i

I call her weezey

2006 BMW Z4 3.0i Roadster - Sold and I miss her.

Last edited by RufusKing; 12-14-2012 at 11:14 AM.
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