Aftermarket head unit radio reception problems.

[weevil]

Originally Posted by kevinj93

The blue wire in that adapter is the power feed to the antenna amplifier. From memory, this is a black wire parallel to the actual antenna cable. The radio normally feeds 12v to this wire. If there is no 12v feed to this, you will have very poor radio reception. Look for a switched power output from the radio. This will possibly be labelled as being for amplifier switching. Connect this to the antenna amplifier wire.

I missed this one when I installed an aftermarket radio. Once I found it, the reception was almost as good as the stock radio.

Yep that is my understanding too, I have tested the wire and it’s definitely getting 12v but the signal is still nowhere near the factory unit.