Radio AM band reception is bad

It sounds like you have a problem with the AM portion of the radio which with vary depending on which radio you have. Here are the radio wiring diagrams for both unit is case. Here is a guide to help you test the wiring to confirm the failure, check the black antenna wires:

https://www.2carpros.com/articles/how-to-check-wiring

Check out the diagrams (below). Let us know what happens and please upload pictures or videos of the problem.

Cheers, Ken