Wife hates the new Kenwood HU because of the crap FM reception. 'Cmon, please help me out here! I know that there are a lot of forum members like myself that did a HU upgrade. Did your AM/FM reception stay the same? Better? Worse? Let me know please... I would like to get this figured out and fixed.

 

Last year I upgraded my Liberty with a Kenwood DDX9703S and my Corolla with a DDX574BH. I've had no AM/FM reception problems with either, reception is equally good. I had both installed at Best Buy. I live in Los Angeles County where getting reception is pretty easy anyway but I have since driven cross-country with it and had no problems. I upgraded the Jeep so that I could use my aftermarket rear camera.

The only problem I have is that when I'm listening to something on my phone via Bluetooth. the HU (mostly the Corolla's DDX574BH) will drop out of BT into an AM or FM station that is doing a test. Many times it's a station I don't even listen to or have programmed into the HU.

 

Also, you might want to check to see if there is an install video for your HU from the guys at Five Star Car Stereo on YouTube. I watched their videos to help decide which HU I wanted to buy. I also contacted them with questions I had (even though they are in Florida and I'm in California). They responded pretty quickly on Facebook.

 

Thanks, but this is not related to a different model of vehicle, like Corolla, nor related to the reception of various aftermarket HUs. I've done installs with various HUs on various vehicles with zero problems.

This is "a Jeep thing" problem, specifically related to the fact that there is a wire on the KK harness at the radio labeled antenna amplifier, and / or the dual purpose stubby satellite / radio antenna.

There are posts on the internet from a number of other people that have experienced the same problem as myself with an aftermarket HU on a KK liberty, but unfortunately none of those posts that I found has received a solution reply (just other people chiming in that basically say "me too").

 

Thanks, but this is not related to a different model of vehicle, like Corolla, nor related to the reception of various aftermarket HUs. I've done installs with various HUs on various vehicles with zero problems.

This is "a Jeep thing" problem, specifically related to the fact that there is a wire on the KK harness at the radio labeled antenna amplifier, and / or the dual purpose stubby satellite / radio antenna.

There are posts on the internet from a number of other people that have experienced the same problem as myself with an aftermarket HU on a KK liberty, but unfortunately none of those posts that I found has received a solution reply (just other people chiming in that basically say "me too").

All right I don't have the radio myself but what I do have is somewhat/decent amount of an electrical basis. So let's begin with the basics for my sake and work from there. I need your exact radio and your model year and what you have already done and wire color for amplified antenna and etc.

The antenna itself sounds wired up and that only leaves the amplified antenna. In my experience at least you DO have to apply power to it as the Antenna needs power for a good reception. The Subaru's antenna is the same and people complained of horribly reception if you don't hook it up but the jeep might be different. Before you do anything however let me get all the information so I don't give you bad advice and accidentally mess things up because in my experience every car is different because they don't understand standardization.

 

OK, Lets see if the antenna is getting 12V after the install of your aftermarket HU unit.
It is real easy to get at the antenna connector.
Open the rear hatch.
Look at the top plastic peace at the top of the center of the opening of the rear of the jeep.
You can just pull it down it snaps into place.
You can move the headliner down a bit in the center and use a flashlight to locate the three cables going to the antenna. ( you might have to remove a round retainer. Just be slow and don't break it. but if you do don't worry those are easily obtained at auto parts stores.
One will be a small coaxial cable (that's the sat antenna for XM or sat nav) And a larger coaxial cable roughly twice the diameter of the sat cable.
The will the the Radio RF cable. Now here is the wire that supplies the power to the amp that is in the antenna.
You will have to disconnect the little connector on that cable to the antenna.
If you have a volt meter or even just a lighted 12V probe you can see if there is 12v DC+ there by checking from any cassis ground point of the Jeep.
If you do have 12V+ there then there is a possibility that the antenna is not getting a ground connection.
It gets its negative return (ground) from the shields of one or both of the other two coaxial cables.
If the new HU unit has a floating ground on the RF receiver this will prevent the amplifier from getting a Ground return for the power.
The only way to test this is to measure continuity from the shields of the coaxial cables to chassis ground.
I know ai am really getting into technical territory but this is what I am suspecting what is happening.
Any good audio installer would know this.

 

Yes, I will need to check, but without checking, I would have to say that it is NOT getting 12v, nor do I know if it is supposed to get 12v. Basically the factory harness has a wire labeled "18GY/OR AMPLIFIED ANTENNA FEED" (see screen shot). The aftermarket harness that attaches to the factory harness does not have a wire that connects to that wire. My thought is perhaps the factory radio outputs power to that wire, which goes to a signal amplifier. I am not knowledgeable in antennas beyond the normal part of a radio install that says "disconnect mast antenna cable from back of factory radio, and plug into new aftermarket radio", which I did, but this not your normal old school mast antenna that is attached to the front fender. It's some kind of dual purpose antenna that may or may not have an amplifier built into it like the powered rabbit ears for my TV.

Most older vehicles have just a single antenna cable to the factory radio, but this has 2 and they are the same connector with the exception of one being white and the other being orange in color (same diameter of cable where they both connect at the radio, not larger as you describe what I should find at the antenna itself.

Considering that an aftermarket radio is probably the #1 modification to any vehicle, my hope was that this is such a common problem to the #1 KK modification, that the solution would be soooo easy to find.

So if you are saying that this gray and orange wire runs all the way to the antenna itself, and there is 0 volts at it, then it would need power to it because then that means that the amplifier is built into the antenna. The question then would be how much? I cannot safely assume it's 12 volts and just connect 12v to it right?

 

BTW, debinvenice, I apologize if my reply seemed rude to you. I did/do realize that were indeed trying to help. Thank you.

 

The wiring diagrams pdf nor the antenna systems pdf show voltage to the amplified antenna feed wire. I think the answer would be to have measured voltage at the amplified antenna feed output of the factory radio where the gray and orange wire would connect to it, but that is no longer an option for me.

 

I am currently running some new two way radio cables in the jeep and have access to the regular radio antenna.
I pulled the connector off and measured the voltage while the radio was off and when it was on.
When it was on there was 12.3Vdc And when the radio was off the voltage was 0.
This was with the jeep just in acc not running.
Hope that helps.
I would first unplug your wire and use a long wire with your meter probe and with the jeep off and the negative battery terminal off.
Do a continuity test from the wire color coded as power for antenna at the HU connector. And the connector at the antenna.
If it passes the test then I would get a inline fuse holder and put in a 1A fuse and tap off of the 12v accessory plug that is on the front bezel
That is switched with the ignition.

But I would test and make sure that sending 12v to the antenna fixes your reception issues before making any permeant changes.
Good luck.

 

BTW the label 18GY/OR just means position 18 in the connector with the main color of Grey with an orange stripe. I am pretty sure about that.

 

Yes, correct.

Thanks for the help! Appreciate it!

 

I had the same issue with my 2008 Jeep Liberty. Finally took it to an auto electric shop. The fix is simple. These antennas are amplified and the power is supplied by a 12V line from the OEM radio. They just ran a new line from the fuse box to the antenna power line. Fixed.

 

I know it is an old thread but verified head units (can bus mygig years) provide 4.7 volts to power wire to antenna whenever radio is on the factory head units do not provide 12 volts only just under 5 volts
Verified on 4 different mygig oem head units on connector pin 7

gray with orange stripe

Cav	Circuit	Gauge	Color	Function
1	A116	14	YL/RD	FUSED B(+) (I.O.D.)
2	D264	20	WT/OR	CAN INTERIOR BUS (-)
3				-
4				-
5				-
6				-
7	X62	18	GY/OR	AMPLIFIED ANTENNA FEED
8	X205	18	GY/LG	LEFT REAR SPEAKER (+)
9	X295	18	GY/DG	LEFT REAR SPEAKER (-)
10	X206	18	DG/LG	RIGHT REAR SPEAKER (+)
11	X296	18	DG/GY	RIGHT REAR SPEAKER (-)
12	Z910	18	BK/WT	GROUND
13	D265	20	WT/GY	CAN INTERIOR BUS (+)
14				-
15				-
16				-
17				-
18				-
19	X202	18	DG/VT	RIGHT FRONT SPEAKERS (+)
20	X292	18	DG/YL	RIGHT FRONT SPEAKERS (-)
21	X201	18	GY/VT	LEFT FRONT SPEAKERS (+)
22	X291	18	GY/YL	LEFT FRONT SPEAKERS (-)