I’ve decided to install a CarPlay module in my 2015 C450. The Aux port is deactivated, so need to use a USB to AUX connector which comes with the module. But what happens if I activate the AUX port as I’ve read it’s possible to do? Do I need to connect any other cables or will it work directly without using the USB to AUX connector.

 

If you have the AUX feature activated.
You will need to add a physical AUX wire to the back of the quadlock connector on the headunit.
3 pin outs, left audio, right audio and a ground.