Question about antenna adapter

[rjay]

I've got a 2009 Nissan Sentra and am installing an aftermarket HU. Came with antenna adapter, Metra 40-NI12. It has the normal antenna plug coming out of it, but also has a blue wire (antenna booster I believe), what does that connect to? Thanks

[GreenBook]

You sure it's not the turn-on lead for a power antenna?

[rjay]

I'm not sure. The instructions don't say what to connect it to, it just refers to it as an antenna booster.

[keep_hope_alive]

antenna boosters are powered antenna amplifiers that connect to the power antenna wire (blue).

[rjay]

Okay, forgive my ignorance! So instead of connecting it to the red 12v wire, I need to connect it to the blue wire from the HU that's labeled power antenna?

[-01limited-]

correct

[rjay]

Thanks alot, I will try that when I get off work

[rjay]

So I swapped out HU before trying it, but I got the HU in yesterday and connected the antenna booster wire to the power antenna wire and didn't gain anything! For some reason the reception goes downhill when I have it connected to an aftermarket HU. This is the third one (all different brands), and I lose reception on certain stations. But when the factory unit is installed, reception is fine. Any ideas? Maybe I have to stick with the factory radio and just wire the amp up to that! I don't know. Was really hoping to keep this new unit (which is Kenwood DPX308U), but I definitely need the fm signal to come through!

[keep_hope_alive]

maybe the factory radio antenna is a different impedance. i haven't encountered that before. more likely, the factory antenna has a built-in booster and the factory HU gives it power through the antenna wire. without that power the antenna may not function and the reception you get is just from the coaxial wire (which is shielded). i'm sure a search in some Nissan forums would hash that out.

you can buy external FM antennas that mount to the rear (or front) glass and just bypass factory antenna completely.

[rjay]

Yeah I've checked a couple of Nissan forums, but didn't have too much luck. I may look into bypassing the factory antenna idea. Thanks for the help

[keep_hope_alive]

well, yea. since you had to buy an adapter that required voltage, the blue wire is for the factory antenna booster. not sure why i didn't put that together last night.

try connecting the blue wire to ignition instead of turn-on. if that doesn't work, bypass the antenna.

[rjay]

So I connected it to to turn ignition turn on, and it definitely boosted the reception! So far, I haven't lost reception and it's playing like it should, I really appreciate the help.

[TheUnderFighter]

Great to hear that worked for you!
I was just gonna suggest you stop listening to the radio:P At least where I am from, the reception on everything is terrible, and I hate the music selection every station has anyways. The only thing I use my radio for is listening to the ball game on the AM.