OT Electrical Question - Maybe You Guys can help?

This is off topic. I just returned from a great trip up to Cutler, Maine (thanks Jim-ME for the great advice on where to hike).

About 5 months ago I replaced my FJ's radio with a Pioneer Avic X710BT nav unit. I love everything about it with the exception of one thing - I get a lot of FM static.

What could cause this? It seems hyper-sensitve to changes in altitude (ie - I go over a hill and I get great reception, the road goes down and I get the snap-crackle-pop effect). AM is fine, as is iPod etc. Only happens in FM. I even noticed today that my winshield washer pump made it hiss on a certain station. Is this a grounding problem? My antenna is screwed on tight, and the plug is tight into the back of the radio. Thanks in advance for any help - the FJ guys weren't too helpful...

yes, sounds like one to my untrained eye. see what the experts weigh in with.

the fact that 1 accessory is giving you problems while others aren't does sound like it's ground related. you mention am is ok, but not fm. wondering if am really isn't ok, but how much time do you spend listening to it? (assuming you aren't a talk radio guy).

have you thought about investing in a DMM? i've avoided doing so because haven't had need...yet. that said, they will help you find voltage/resistance issues pretty darn quick.

It's pretty tough to diagnose these type of problems remotely. Some things to consider or investigate would be the antenna connectors ( see if moving the connector while listening to the radio has any effect). Is the head unit properly wired with the correct adapter? Is there a built in antenna amplifier in the FJ? If so is it powered? Remember FM signals work on a straight line so interference is possible with ground obstructions, especially if the antenna is not optimal. Last, you could have a defective head unit, it happens.

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Originally Posted by kevkon

It's pretty tough to diagnose these type of problems remotely. Some things to consider or investigate would be the antenna connectors ( see if moving the connector while listening to the radio has any effect). Is the head unit properly wired with the correct adapter? Is there a built in antenna amplifier in the FJ? If so is it powered? Remember FM signals work on a straight line so interference is possible with ground obstructions, especially if the antenna is not optimal. Last, you could have a defective head unit, it happens.

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thanks for the reply.

I forgot to mention the FJ has no amplified antenna - that was my first thought as well. All connections are good with the antenna.

Maybe I should redo the grounds for the unit and maybe the power leads as well? Would that possibly help? Or if that were a problem would it be causing interference with all forms of audio? (am, iPod, etc)

Curious, how was the original Toyota stock radio for FM reception?

A few years ago I updated(?!) my original Audi head unit in my S6 with a Kenwood CD unit and the FM reception just dropped off like yours. With the original Audi Bose / Blaupunkt Gamma unit, the classical station in Stowe would always come in great. Now it comes in but, not as strong and lots of static.

Turns out the Blaupunkt Gamma original unit had twin antenna's, using one in the front windscreen and the rear aerial stick, these possibly were tuned to the head unit.

I almost want to revert back to the original setup, gain back great FM reception, ditch the single CD player and just hook up my latest iPod.

Also, FWIW, the original single antenna Blaupunkt in my 1991 Volkswagen Westfalia pulls in FM signals like a freight train and any and all Blaupunkts I've owned seems to do the same.

ps.. moved thread to General Discussion

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Originally Posted by TSR53

Curious, how was the original Toyota stock radio for FM reception?

A few years ago I updated(?!) my original Audi head unit in my S6 with a Kenwood CD unit and the FM reception just dropped off like yours. With the original Audi Bose / Blaupunkt Gamma unit, the classical station in Stowe would always come in great. Now it comes in but, not as strong and lots of static.

Turns out the Blaupunkt Gamma original unit had twin antenna's, using one in the front windscreen and the rear aerial stick, these possibly were tuned to the head unit.

I almost want to revert back to the original setup, gain back great FM reception, ditch the single CD player and just hook up my latest iPod.

Also, FWIW, the original single antenna Blaupunkt in my 1991 Volkswagen Westfalia pulls in FM signals like a freight train and any and all Blaupunkts I've owned seems to do the same.

ps.. moved thread to General Discussion

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original radio's reception was very good, but it's not known for being that good amongst Toyota owners (so if this Pioneer's supertuner is worse than it, there's something wrong). The Pioneer pulls a LOT of stations in - for example when I seek, it will stop on stations 40 miles away. But then as I'm moving I get the 'shhh shhh shhh" sound. On top of that, I have a separate HD radio tuner (it's an add-on module behind the dash) so not only do I have reception going in and out, but I also have it changing from analog to digital to static to analog.....etc. The odd thing is that the strongest stations will come in just fine....


btw an S6 is a great car...

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Originally Posted by Bostonian1976

The odd thing is that the strongest stations will come in just fine....

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That's really not odd at all. The digital receivers will tend to clip off all but the strongest signals. Fm reception is unfortunately not really better with a lot of the aftermarket head units, especially those loaded with other sources. It's kinda like the cell phones, sometimes just getting and making a call gets the lowest priority. I guess the radio mfrs feel, who needs radio reception anyway? When I have run into this problem with an install I can sometimes overcome it with a good external antenna. Sometimes not. It also has a lot to do with where you are located and the strength of the fm signals.

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Originally Posted by kevkon

That's really not odd at all. The digital receivers will tend to clip off all but the strongest signals. Fm reception is unfortunately not really better with a lot of the aftermarket head units, especially those loaded with other sources. It's kinda like the cell phones, sometimes just getting and making a call gets the lowest priority. I guess the radio mfrs feel, who needs radio reception anyway? When I have run into this problem with an install I can sometimes overcome it with a good external antenna. Sometimes not. It also has a lot to do with where you are located and the strength of the fm signals.

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The thing that makes me think there is a problem is the similar sort of static I get across multiple stations.

It's a series of what I'd call "pops" and "shhhh shhhh shhh" in no particular order....

also - has anyone ever tried an inline antenna isolator? It's supposed to help where a ground loop might be a problem...which could be the case here right?

Honestly, I've never had a ground loop problem with an auto radio. That's usually something that occurs in an ac to dc situation. Do you have some reason to suspect that your chassis ground off the head unit is bad? If so check the resistance or just run a new ground. Personally, I think you should be looking at those things which are unique to the new system as I believe you said the oem unit did not exhibit this interference. I'll add this, the one time I had a problem similar to what you have described it turned out to be a bad antenna connection. The connector looked fine, but in fact was not making a proper connection. Replaced the cable and all was fine.