How do I get the aux to work in my car?
Why does my aux keep switching to radio?
One possibility is that you have accidentally activated the AUX mode button on your car stereo. Another reason could be that there is a problem with the car stereo’s wiring, which is causing it to default to AUX mode. Finally, if you have an aftermarket car stereo, it is possible that the AUX input is faulty.
How do I add an AUX port to my old radio?
If your stereo has RCA input ports on the back, you can simply purchase an adapter cable that will plug into the RCA port and your music playing device through a 3.5mm male cable. Many cars came with ports for CD changers.