My 2004 TSX has the exact problem described by others several years ago concerning popping in the speakers when the A/C condenser fan cycles off. It only occurs when the audio system is powered on and the A/C is on. It is not the fan for the hvac, it is the A/C. Vehicle ground is fine. Previous threads did not solve this issue. Any suggestions?

 

Sorry to hear you're having the same problem that I'm having with my '06. You get a "pop" sound through all your speakers when the a/c clutch disengages on your fan, not when it first turns on, only when it turns off. I'm assuming you're referring to the thread I started years ago:
https://acurazine.com/forums/audio-video-electronics-navigation-22/speakers-still-snapping-any-electrical-experts-out-there-388497/
I never was able to solve the issue going through honda/acura directly. They consulted their engineers after seeing that others had solved the issue by installing a diode into the ac line that runs back out of the compressor fan. The theory is that the diode in our AC field coil system has failed and is allowing back current into the audio system which eventually shorts out the AC clutch relay in the engine compartment (the relay starts to arc) . However, even though they completely replaced the compressor parts that supposedly contained the failed diode in my car, the noise still remained. So unless you have an electrical expert that you know of, the after market solution is to just install a diode in the line like others have done in the thread referenced above. You can also replace the relay that is failing (it's part #39794-SDA-A03). But that's just a temporary fix (maybe a week or two at best) because the electricity being fed back into the line will eventually make the relay fail again. I hate honda for not being able to fix a problem that any good 3rd party mechanic can identify. My guess is that there's another diode that's failing as well, but you could just try the fix that others have done here on the forum. It's permanent for them for some reason, even though honda's fix for me was essentially the same thing. Let us know if you get any additional info!

 

Jottle, indeed I had carefully read the thread you started on this issue some time ago. I very much appreciate your response, in that it can save me expense and frustration with changing parts and trying to find grounds to this that and the other. I agree that Honda/Acura should have been more helpful in resolving this problem for you and all of us who deal with it, but auto manufacturers have a habit of burying their heads in the sand in so many cases. One of the greatest things about forums such as this is that we can really help each other to avoid endless frustration in treating problems with our cars.
Did installation of the diode in the A/C line provide a real fix for you? If so it sounds like a rather uncomplicated solution to a problem that has confounded you (and others). I must say that I just don't turn my radio on--ever! due to the frequent speaker pops.
Once again, many thanks. I will respond if I get it resolved or if I can add others words of wisdom.

 

I never tried putting in the diode myself. But everyone else who has done it reported that it was a permanent and lasting fix. However, reading what you're describing is happening in you car, it may be a slightly different variation of the problem. At least in my situation, the speaker pop when the ac compressor fan shuts off regardless of whether or not the audio system is on or off. From your description it sounds like you get the pop only when the audio system is active. Could be a ground issue...not sure.