I upgrade my 4 inch screen to Sync 3 8 inch. I installed with an aftermarket harness. Everything works but when I use the handsfree voice activaction, I can’t hear callers, and the voice activation does not come on. It hears me but I can’t hear it. I noticed on the cable that attached to the back of the 4 inch screen had 6 wires attached to it. But the connection it attaches to on the upgrade harness only has two wires and that is for the back-up camera. I bought a second harness, reset my system 3 or 4 times and it doesn’t work. I reinstalled the 4 inch system and everything works.

 

Can you take it apart again and take pictures showing factory setup and 8 inch screen setup, particularly the wiring.