Poor FM Reception After Head Unit Upgrade

[loarmistead]

UPDATE: Resolved in post #13

I installed a Pioneer touch screen head unit into my 2006, and purchased the small antenna plug adapter and the Y-adapter so that both antennae were connected to the FM plug on the back of the head unit. Problem I have since encountered is that reception is horrible, as if one of the antennae isn't functioning. Has anyone else experienced this?

Local low frequency station I can pick up clearly all over town in my other vehicle gets fuzzy in spots around here, and most annoying of all, my favorite station, which is HD on the same frequency, kicks in and out HD frequently due to the shoddy signal, and is not pleasant to the ear. Other stations further away that I can still pick up around town in other vehicles do not come in at all on this new unit - pure static.

 

[fAr eAst rUnnEr]

I know when I upgraded my head unit that the space was behind it is pretty tight. Might be worth it to remove it and make sure that nothing came unplugged while jamming everything back there.

As far as the Y adapter is concerned I know its not necessary so you might try taking that out of the equation and see if the reception is better before reinstalling everything. I have played with using the adapter and not using it and found no difference in reception although I am currently using it for no other reason that I paid for it so might as well.

 

[Trumpet]

When I did my HU upgrade (also pioneer), I found there was a wire bundled with the two antenna leads. That wire needs to be connected to the 12v blue/white control lead off the HU harness.

Our 4runners have a amplifier module in the rear quarter that needs to power up to provide good reception. Once that was done, I left the little antenna wire disconnected, as it wasn't needed in a non-Diversity receiver.

 

[loarmistead]

When I did my HU upgrade (also pioneer), I found there was a wire bundled with the two antenna leads. That wire needs to be connected to the 12v blue/white control lead off the HU harness.

Our 4runners have a amplifier module in the rear quarter that needs to power up to provide good reception. Once that was done, I left the little antenna wire disconnected, as it wasn't needed in a non-Diversity receiver.

Very helpful! I recall the two antenna leads being wrapped in foam (nice touch), but do not recall seeing the wire. I will pull the HU out this weekend and take a look. Do you happen to recall the color of the wire?

 

[backcountrymedic]

Did you get a wire harness adapter to plug into the factory harness? I got one, and it had instructions on how to wire that up specifically.

 

[Trumpet]

Very helpful! I recall the two antenna leads being wrapped in foam (nice touch), but do not recall seeing the wire. I will pull the HU out this weekend and take a look. Do you happen to recall the color of the wire?

It was dark colored, and bundled with one of the antenna leads. A single connector on the end.
[MENTION=154211]backcountrymedic[/MENTION] , there was no accommodation for it in either the pioneer or the crux harness. A chat with a Crutchfield CSR, brought the info to light.

I also found it mentioned deep in a install thread here, but didn't save the link.

 

[DMX512]

I believe that the automatic/ power antenna wire needs to be connected. Blue/Wht if I recall correctly. I used a Metra harness adapter. Reception greatly improved after hooking up the power antenna leads. I think that is what [MENTION=150815]Trumpet[/MENTION] is referring to.

 

[DMX512]

Try this link
http://www.toyota-4runner.org/4th-gen-t4rs/226119-how-everyones-radio-reception.html

 

[DMX512]

Or try this link
http://www.toyota-4runner.org/engin...ity-antenna-reception-fix-aftermarket-hu.html

 

[Trumpet]

Skip the metra adapters and just power the wire from the blue/ white from the hu. Without a special muxing rf amp (diversity amp) all paralleling the antenna leads does is further degrade the signal.

 

[catfishbirddog]

Hmm. I just plugged the one antenna wire that fit the female plug on back of Pioneer and left other one unplugged, it seems to work just as well as it used to. But I haven't listened to much radio on it...flash drive usb with music and movies for days, apple carplay, dvd, bluetooth and aux have given me more options than I can handle!

Edit - after reading the thread linked above, sounds like my PAC harness is probably already powering this antenna amp that I didn't even know I had. I have limited that came w/ JBL amp and navigation.

 

[DMX512]

Just to clarify, I do not have the JBL system from factory.

 

[loarmistead]

RESOLVED

For posterity's sake, this was a stupid easy fix. There is a solid blue wire on the aftermarket harness from Crutchfield that says "power antenna" on the insulation. I wired it in with the existing blue/white power wire and BAM. All stations come in clear as day.

Like many others, I thought this power antenna wire was for cars like 3rd gun 4Rs with the retracting power antenna. Thanks for all the help.

 

[simple]

What do you mean 'wired in'? I installed a scion pioneer radio and my reception isn't awful, but its not awesome.

 

[loarmistead]

What do you mean 'wired in'? I installed a scion pioneer radio and my reception isn't awful, but its not awesome.

The harness blue/white power wire was already tied into another blue power wire per spec, I just took off the wiring cap and twisted the "power antenna" blue wire in with the other two blue wires, and the problem was solved.

 

[DMX512]

Glad you got it resolved. It is pretty counter-intuitive but it works.

 

[riceandpho]

The harness blue/white power wire was already tied into another blue power wire per spec, I just took off the wiring cap and twisted the "power antenna" blue wire in with the other two blue wires, and the problem was solved.

or you can just use the acc wire for that too.

 

[simple]

:lol:

or you can just use the acc wire for that too.

Bump bump bump

Is there a trick to the ACC wire? I’ve never installed a radio in my multiple 4runners, scion or aftermarket, that didnt suffer from poor radio reception. I did some tests and after hooking up my antenna power wire my reception improved but only marginally. I only pick up about 3-5 stations depending on my location, but they’re staticy, and still drop out. I also live near San Diego and there’s plenty of stations to go around, if I’m in wife’s car, they come in crystal clear.

I want to try the acc wire, but feel like I may have already, tying in the power antenna wire and the radio turned on with the car off and key out of the car ignition. Does the acc wire power anything else? Because when you’re did it, I had the red or yellow wire(can’t remember color) connected to each other and just mixed in the antenna wire.

 

[riceandpho]

:lol:

Bump bump bump

Is there a trick to the ACC wire? I’ve never installed a radio in my multiple 4runners, scion or aftermarket, that didnt suffer from poor radio reception. I did some tests and after hooking up my antenna power wire my reception improved but only marginally. I only pick up about 3-5 stations depending on my location, but they’re staticy, and still drop out. I also live near San Diego and there’s plenty of stations to go around, if I’m in wife’s car, they come in crystal clear.

I want to try the acc wire, but feel like I may have already, tying in the power antenna wire and the radio turned on with the car off and key out of the car ignition. Does the acc wire power anything else? Because when you’re did it, I had the red or yellow wire(can’t remember color) connected to each other and just mixed in the antenna wire.

yellow on aftermarket radio is constant hot 12v.
red is the accessory.
when you put the key in acc, things will turn on is the 12v plug and radio. also clock should display on the hvac.

 

[simple]

yellow on aftermarket radio is constant hot 12v.
red is the accessory.
when you put the key in acc, things will turn on is the 12v plug and radio. also clock should display on the hvac.

How do I power antenna with acc wire. Just tie it in?