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MF743Cdw Fan Running Continuously


I recently purchased a imageClass 743Cdw and noticed that the fan runs continiously even in sleep mode. similiar to MF733Cdw Fan Running Continuously post. Unfortunately that post ends with no useful information and an EcoStar device should not be really running a fan continously when in sleep mode. How do I get the fan to stop short of turning off the power?



Thanks but there is no document referencing anything about sleep mode or fans in the knowledge base and the support team couldn't provide any more detail other than update firmware (which I have already done). I can't even get some one to tell me if this is by design (expected behavior) or is an anomaly. So I guess i will just return the device then.

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We tried one last effort - resetting the machine to factory settings. While I lost all my settings and will have to put them in again, the fan stopped running. Obviously there is a software bug in there and I am hoping that one of the options I setup previously is not going to cause the fan to run again - but for now it is fixed.


I should also mention that the gentleman on the support line was great.

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Are you sure you did a full factory reset? Try one more time. Also post your firmware version. 

I initialized the settings a second time and did the basic language and time selection. The fan now shuts off while in sleep mode.

Fantastic! **bleep** glad to hear it!


I believe there's definitely a firmware bug here - and it would be great if Canon would investigate/ fix it.  It's related to using the fax function. Out of the box, the fan works normally - and stops spinning when the machine goes to sleep.  Once the fax function is used, the fan never sleeps.  I've reset all the settings and the continuous fan goes away.  However, using the fax function again causes the fan to spin forever again and the only way I've been able to stop it is by factory resetting the entire machine again.  Obviously, completely factory resetting the machine after every sent fax is not an acceptable workaround.  Soon after I got the machine, I called customer service and explained the issue.  I don't think they understood and/ or never escalated the problem.  





Receiving faxes should not make the fan run all the time. In this situaion, it would look like there is a problem with the hardware. I would suggest contacting our support team at 1-800-652-2666. Our agents would be happy to provide service options for the printer.

Hector - Thanks for the reply.  I've had this problem since purchasing the machine several years ago.  I actually did call your support team shortly after purchase (I noticed the problem right away) and they were not particularly helpful.  I'm pretty confident it's a firmware problem and not a hardware problem - particularly because after factory resetting the machine it works fine, and continues to work fine until using the fax function.  I would ask that you have someone at Canon try it out:  set up the machine, plug it in to a phone line, send a fax.  After that, the fan will not stop spinning, even in sleep mode.