Oldsports

Can anyone tell me the functions of the antenna connections on my 2005 RX330 non-ML, non-Nav radio? There are two antenna connections on the back of the radio. One of the connections appears to be the radio antenna but there is a second, smaller connection right next to it.

Thanks!

rich001

It's a diversity antenna system, I believe the larger one is for the antenna on the roof, and the smaller connector is for the antenna in the rear window. If you are planning on replacing the factory stereo, just use the larger connector. And I believe it's a powered antenna, so you also need to hook up a power antenna lead wire to your new stereo (I'm not sure of the color code off hand).

Oldsports

rich001,

Thanks for the reply. I replaced my OEM head unit with an aftermarket unit and I have noticed a decrease in reception. I just did some quick research on the Internet and found out how to connect both connectors with a Y-cable so that both signals can be fed into my aftermarket unit.

As far as providing power to the antenna, I'll need to do a bit more research. I did not wire my aftermarket unit directly to the radio harness. Instead, I installed a Metra TYTO-01 interface to connect to the radio harness. I am using my OEM amp and speakers; the TYTO-01 makes the aftermarket unit look like an OEM head unit and provides the proper inputs to the amp. I don't know if the Metra interface provides an antenna power input to the radio harness but I would have hoped that it did. Unless you (or someone else) knows the answer, I will contact Metra to see what they say.

By the way, what is the power used for? Is it used to boost the signal from the antenna?

Thanks!

rich001

The roof mounted antenna is an amplified antenna system, as log as you connected the Blue/White wire of the TYTO-01 to your aftermarket stereos Blue/White output wire, it should be okay. Yes, even my reception got worse, but I just listen to other music sources.

Oldsports

rich001,

I did connect the Blue/White wire of the TYTO-01 with my aftermarket's antenna power wire. The TYTO-01's instructions describes the Blue/White wire as the "amp turn-on" and says that no sound will be heard if this wire is not connected. I sent an e-mail to Metra's technical support with my issue; this is what they sent back to me:

This RX doesn't require any amplification on the antenna. This is no different than any other Toyota product in that aspect. If you're having reception issues, I suggest checking the Motorola jack, or it could possibly be your new tuner. This wouldn't surprise me, as the aftermarkets aren't always as strong as the factory.
JAKE ECONOMOU
TECH SUPPORT
METRA ELECTRONICS
1-800-253-TECH

I am going to connect to the secondary antenna to see if that helps. I ordered some parts from eBay and will install them when they arrive. I will let you know if if makes a difference.

Thanks!

rich001

I looked this up, and the power antenna lead for the RX330 is "Orange", at the harness of the factory stereo. The TYTO-01 must be turning on that wire. If you want to check, just meter that wire and turn on and off your stereo, it should show 12v with the stereo on and 0v with the stereo off. Metra is wrong, cars with those short stubby or shark fin antennas are normally an amplified type, which requires power.

Oldsports

rich001,

When I was doing research for installing the aftermarket stereo, I found this information on the wiring harness:

2005 Lexus RX330 Car Stereo Installation Guide
Car Radio Battery Constant 12v+ Wire: Blue/Black
Car Radio Accessory Switched 12v+ Wire: Gray
Car Radio Ground Wire: Brown
Car Radio Illumination Wire: Green
Car Stereo Dimmer Wire: N/A
Car Stereo Antenna Trigger Wire: Orange
Car Stereo Amp Trigger Wire: N/A
Left Front Speaker Positive Wire (+): Brown
Left Front Speaker Negative Wire (-): Red/Yellow
Right Front Speaker Positive Wire (+): Violet
Right Front Speaker Negative Wire (-): Pink
Left Rear Speaker Positive Wire (+): Red
Left Rear Speaker Negative Wire (-): Gray
Right Rear Speaker Positive Wire (+): Red/Yellow
Right Rear Speaker Negative Wire (-): Blue

As you state, the Orange wire is identified as the antenna trigger wire. What confused me was that the amp trigger wire was "N/A". Given what Metra said about needing to trigger the amp in order to get sound, I expected there to be a wire for that trigger. Since I got sound out of the amp, I did not pursue it any further. I believe your assertion that the TYTO-01 is triggering the Orange wire and I will test that when I remove the stereo to connect the secondary antenna.

Thanks!

naivelin

The two antennas have separate antenna amplifiers. The orange wire is the power+ of both amplifiers. If you use aftermarket radio or navigation systems, you need connect the orange wire to ANT wire of the Head Unit.

metalmagic

I'd be interested to know where you found a Y wire. I can't find one on either the PAC or Metra sites

Oldsports

Metalmagic,

I found the cable on eBay - they have quite a few of them. Here is one for sale: https://www.ebay.com/itm/30cm-Univer...item48a5af41c0

You will also need an adapter for one of the antenna connections because it is smaller than the normal connection. Here is an adapter on e-Bay: https://www.ebay.com/itm/Scosche-MDA...item3f2b782d5d