The other day I hit the auxiliary button on the radio and got no response. The rest of the radio and CD features work fine, but the auxiliary function has ceased to exist. Any ideas on why this happened and how to fix it?
Do you have navigation and an auxiliary input above the glove box? If you have an RTL without nav, I don't believe the aux button on the head unit actually does anything. It's been a long time since I've had the stock radio in my RTL, so I'm a little foggy on this.
I had a similar problem that I just managed to repair today. Albeit, your problem might not be the same. My AUX was shorting out. The jack wiggled around and if I wedged something under it in just the right way, I could get it to work.
I figured out how to replace the part (39114-SJC-A01ZA). You have to pop the clips out of the glove box to drop the glove box. There are two spring clips to the right and the left of the AUX. Press them in and push the AUX out through the front. Then simply disconnect the old AUX and replace with the new. Pop the new AUX in place and replace your glove box. I paid Honda over $40 for the part. But you can also get it here for nearly half: http://www.hondapartsnow.com/genuine/honda~jack~assy~39114-SJC-A01ZB.html
Now I'm not saying that this definitely the problem but if there is wiggling with your plugged in cable, this is the likely culprit. Good luck.