L322 Problem with a little fan inside AC front panel

fpeivissa said:

Hi !!! I ve been listening a noise behind the AC front panel and finally I decided to open it and check it.
There is two boards in it , and in one of them there is a little fan to Cool the board that Never stop running, even with the car key disconnected, and consume battery.
I d like to know if someone can tell me if changing the board or the complete AC front panel this could be solved or if there is any possibility that there is another electric issue outside the board that cause that this fan never stop running.
Thank you !!!!

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robhew86 said:

I'm pretty sure (as Keith says) mine goes off with the ignition.

However, If you lock the car with yourself in it (undo a window just in case it won't unlock you don't want to be stuck in!) press the 'lock' function on the key again quickly once locked to disable the interior movement sensors so you don't set alarm off, sit in there for 10 -15 mins, monitor and check when the gear lever (RED LED) illumination goes out.....the fan should definitely be off by then as all systems are shut down...

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Datatek said:

The fan is supposed to run constantly with the ignition on. It's not for cooling the PCB, it's for sampling the cabin temperature for the aircon. Is should shut down eventually with the ignition off, not sure how long that might be on your car as the BCM takes quite a long time to go to sleep.

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