BMW Repair: 2001 BMW 530i: Sounds like a small fan in the dashboard which stays on when the car is off., 7 digits, bmw 530i

Question
Hi,
I just bought at 2001 BMW 530i and I hear what sounds like a small fan or a similar noise in the dashboard (near the tempature controls) when the car is both on and off. The last 7 digits of my VIN: CF08805. I'm wondering if it being on when the car is off is normal (which I doubt) - but who knows. This is my first BMW. Your help is appreciated!


Answer
Jordan, sounds are impossible to hear over the internet so here are your options or common issues. 1st is the A/C blower final stage resistor keeping the blower on. I would recommend removing and inspecting it to make sure it is of the Newer Aluminum construction and not the old Cast Iron junkers, you'll see it on heat sink fins. If it's Aluminum you all set. If Cast Iron replace it, It WILL fail. Next is the Electronics Box fan (E-Box). Up near the windshield in the engine compartment (under the microfilter housing) is an Electronics box that houses the Engine computer, Transmission Controller, relays, fuses, you get the idea and it has a cooler fan (like a PC fan kind of). So times it shorts out and stays running (bad news when it finally stops). Another is the little fan in the Climate control computer for the interior temp sensor. Never seen this one stay running, but I suppose it could happen. And yet another issue is the the condenser/auxiliary pusher fan shorting out and staying on. This should be easy to diagnose because it will kill you batter like the Blower final stage will. There you have it. Don't worry your car won't experience all of these or maybe any. You need to have someone help you pinpoint/diagnose the noise.
-Evan