Newbie here with an old but good 2004 G35 Sedan, bone stock, 112K miles with a non Bose radio. Have just read several threads on this forum about the dreaded HVAC/radio problems. My HVAC/fan controls work perfectly ALL the time. I never use the CD or tape player and only occasionally use the FM radio tuner. Both the radio tuner and display work intermittently with decent (for a stock radio) sound quality whenever they do work. When they don't work, "AUX" pops up on the display and there is a periodic "electronic burp/screech" sound like there is a short or loose connection in the power supply or ground. The problem occurs whether the radio power button is on or off. Leads me to believe the problem is maybe somewhere in a "constant on" power circuit that supplies the radio? Because I don't use the radio much, I prefer avoid the double DIN aftermarket expense and definitely will never take it to a dealer. I basically just want to get rid of that annoying screech, even if the radio no longer works. Even though I'm trying to fix on the cheap, I’m also concerned about doing anything that might screw up the working HVAC. I've seen some posts about resistors on the circuit board that come loose/unsoldered and some of you electronics savvy guys say you have fixed by reflowing the solder joints. Could this be the problem and a possible fix? I've done lots of soldering on copper/brass pipe joints but never worked on electronics. Is the soldering process the same but just on a smaller scale? Or is there a way to just bypass the radio circuit while maintaining the currently working HVAC circuit? Thanks for any help you may offer.

 

Problem solved. Issue was in the radio itself, not the underlying board. Replaced with a non Bose re-manufactured radio/CD changer from eBay and everything now works fine.