That's the one I got hooked up. When it gets to the aftermarket harness, it switches to blue.

 

When I unplugged my antenna, I lost all signal even worse, so it's got to have some kind of power going to it, and same goes for that orange antenna wire. When I disconnected it from the blue wire, the signal got worse.

 

I would check the antenna on the roof of the car to make sure it is secured all the way and not damaged in any way.

Do you know the history of the car? Has the headliner been removed for any reason? i.e. to be recovered, or hail damage, etc.
If so, then maybe the connections at the antenna were damaged or knocked loose.

A third possibility is that something happened to the AM/FM tuner on your radio between cars, you can go to Autozone, Best Buy, Radio Shack, or places like that and for $10 - $15 buy a universal replacement antenna and plug it in to determine if the tuner is working properly, if you plug in the new antenna and the your reception is the same then it may be the tuner, if reception is better then it the antenna or antenna cable on the car.

Hope this helps.

 

if you disconnected the antenna and it got worse, then you know its connected, and if you disconnected the orange from the blue, then you know it is powering the orange wire.. sounds like a weak tuner in the radio, or just a weak antenna in the car.. try getting an aftermarket metra amplified antenna

metra 44-ua20
or
metra44-ua200

it plugs into the unit, then has a blue wire to hook to your power antenna wire, then sticks on your windshield.. i've done a few installs where i just installed it under the dash close to the top and it worked fine

 

The antenna on the car, or the headliner has never been messed with. I purchased the car brand new a year ago with 44 miles on it.