pagan

Hi,

I have a 2004 530d touring whose CCC unit is overheating when the temperature outside is high, causing all sorts of problems like the the sound randomly stopping for a while, the controls become unresponsive, the jogdial loses resistance, and sometimes the unit reboots itself. This problem only happens with hot weather and I began to notice it during last year's summer.

My car is out of the warranty period so I decided to investigate by myself and see if I could find the cause for the overheating, so I unmounted the dash and removed the CCC unit and found a small fan on the back of the unit. The fan was completely stopped and the unit was already pretty hot so I'm thinking that this must be the problem causing the unit to overheat. I unmounted the fan and connected it other socket that I have on the trunk near the tv tuner box and logic7 amplifier and it works fine. Then I tried measuring the socket that was powering the fan and instead of having 12V it only had around 0.5V. Now I don't know what to do because I already checked the 2 fuse boxes and couldn't find any shorted fuse.

The uploaded picture shows the back of the unit, 11 is the fan and 7 the fan socket.


Does anyone know if the fan is supposed to work at all times or just when the temperature raises above some threshold?
I was hoping that someone here could point me in the right direction.

Thanks

Rudy

It does not operate all the time. He's an exact quote from one of the technical documents:
Electric fan
The Car Communication Computer (CCC) has an electric fan for cooling the audio output stages and processors. The
electric fan is controlled in stages, depending on the temperature of the CCC.

I don't have any more details other than the following document that shows what connector (X13813) and what pins (1, 5 & 11) are used for the fan. It's interesting to note that pin 11 is designated as a diagnostic pin for the fan...

CCC_housing2.pdf

pagan

Thanks Rudy, I didn't realize that the fan was being powered by the CCC unit, the cable that was connected to the fan didn't seem to come from the unit.
The diagnostic pin is probably to read the fan RPM, this is standard on most computer fans.

I think that this fan may be damaged because if I connect it to the socket on the trunk, where I have 12V at all times, the fan only works after I touch it to make it spin.
Would it be too much to ask you for the part number of the fan?


Thanks again.

Rudy

I can't be 100% sure but I think you need part number 6 from the following page:
http://www.realoem.com/bmw/showparts.do?mo...hg=65&fg=45