Can installing a new radio affect my brake lights?

Hello, a wiring diagram would be needed to find out that detailed information. It would seem highly coincidental that the brake lights would suddenly stop working directly after the radio installation. One thing about brake lights is that they are active all the time, just like audio unit memory and lights. It's feasible that there is a related circuit in the area. It's important to note that when a radio is installed, wiring is usually modified to support the radio harness. Again, a wiring diagram is needed to determine what has been done and where to the wiring there. Or, better yet: have the installer recheck their work!

One ODD detail is the transmission should be LOCKED in the park position if the brake light circuit has been compromised.. This isn’t making any sense!