Any fixes for radio static?

? your antenna is top of Prius. FM should be "No Static at ALL" as Steely Dan would sing it (2 Against Nature...grammy album of the year 1999 0r so). We have some radio experts here, so I defer, but is this on AM or FM? If FM I am thinking you have an electrical problem in the car.

 

The antenna cable is attached in the back if the MFD, might be worth it to check it, even remove it and put some dielectric grease on it, check the antenna end also.

 

I recommend the above, and also thinking it could be a loose body ground point somewhere. Of course, something like that would cause problems in other systems too. Wouldn't hurt to break out the 10mm box end wrench and take a tour of the engine compartment, under the dash, and the trunk to loosen and then tighten all those grounding points. If your antenna mast is new, then it wouldn't hurt to put a little dielectric grease on the mating surfaces just to eliminate it as a possibility. I think I read in a thread that there is an integral RF booster in the mast base. Or maybe it's somewhere along the antenna cable. You will likely end up inspecting the entire antenna path. Does your system have an AUX? If so, is there static noise when using it? That would mostly eliminate the antenna path. Good luck!

 

Don't forget their is an active antenna preamp also in the loop. In the 2007 is should be located passenger side rear door up in the roof! If it is bad, well usually nothing is heard at all! Confirm you are listening to NPR on the FM band. How far are you from the stations transmitting towers. What is the stations ERP? If you give me the stations call letters I can look it up. If you are in fringe areas, it could be cochannel interference, but that's not really a static sounding event! If you are on AM, all bets are off. Amplitude Modulation lends itself to static interference by nature of the demodulation scheme.
As mentioned, that's why FM became popular!
Does this happen on all FM channels.... or just this one?
Since I am Mr Radio, lets figure it out!

 

The rear glass only has a heater element, no radio antenna.

 

I replaced my radio in my 2004 Prius with a Pioneer 33HD and when the digital reception turns on, all static goes away in AM. Both AM and FM get CD quality sound when the signal is strong enough for the HD signal to be used.

JeffD

 

Now that you mention it, my home FM sometimes shows "static" when the signal is weak and the station is bouncing in and out of reception...because there is a signal strength meter I can see what is happening.

 

The radio preamp little box is located at the radio in the dash. But try unscrewing the little stubby antenna on the roof and look in the hole of the antenna when you take it off for rust. If you see any spray some lube in the antenna hole and screw on and off a few times wiping off the rust.

Please answer these questions:

Has the car ever been in a wreck? Its not a salvage title right?

How corroded is the undercarriage? Get under the front of the car and see how corroded it is under there. Take some pictures. If very corroded you may have a bad ground connection given the connection to the motor sound.
There's literally hundreds of ground connections in this car.
Also if very corroded under there I would worry about the transmission resolver connector rotting out. A known issue that results in the failure of the transmission.

 

Yeah not to bad rust but pretty corroded at the LCA bushing area. That will rot out and you'll start clunking real bad over small bumps. Shame because its easily avoided by spraying CSP on the under carriage once a year.

See the third photo down with the 2 hoses coming out of the side of the trans. Right above that is the resolver electrical plug. Hose that down with CSP. Don't let that plug dry rot out. The trans will fail.

I will look tonight at the schematic and see where the antenna/radio ground is located. But if hit in the rear take the spare tire hatch off and look in the rear trunk area at all the ground connections and look for rust in the trunk.
There's a bunch.
Remove and clean the big negative cable from the 12 volt battery and sand down the body where that cable mates to it. Grease the sanded area and then bolt the cable back on and apply grease to the negative cable bolt.

 

Yes. I like 100% synthetic wheel bearing grease. Here's the worlds finest grease but any high quality grease works good:


Red Line Synthetic Oil - Grease and Assembly Lube - CV-2 Grease

And PB Blaster CSP spray can be found at Home D. It works great. Does not smell and is a heavy spray grease that will waterproof and stays put. Once a year the entire suspension. No more rust, squeaks or rattles.

And while your under there spray the inner & outer cv joint boots with some Black Magic Protectant. Soak the boot and use a rag and rub it in on the backside too. They look really dried out too. Boot fails the cv joint fails quick.

Its simple stuff like this that can save you hundreds of dollars later.

 

There is no specific ground to the antenna amp. The radio itself is grounded via J36 Junction connector found behind the cowling right where your left knee is under the dash there. 3 wire connector and a brown lead comes off the connector to ground.
Connector has 2 w-b and one brown.

Look under there real good someone may have messed around in there with an aftermarket radio or something.

But I don't like that is seems transmission related. If you had a high voltage leak that may get into the radio especially am but it would throw a code too. I would change out the trans fluid asap and look at it closely and check for burning smells in the fluid.

 

I'm still trying to track it down. I've already cleaned all terminals around the battery in the 2005 and now it's starting in the 2006. It began right after I had the battery changed a few years ago, but the weather also changed at the same time. When I took the car apart to get to the battery last month I found some really sloppy workmanship including a very loose bolt where a bracket is supposed to be secured to the top of the Panasonic antilock brake module. They had also put the negative terminal on backwards so the whole area had to be disassembled and the battery removed just to clean and tighten the terminals. I sanded the area around the cable that connects to the chassis and even put some zinc chromate primer on the bare metal. That's just how seriously I did this.

This is NOT spark plug noise. It sounds like arcing brushes in motors and generators. Instead of thinking engine or transmission, think complex electrical. Put the MFD in the mode that shows a graphic of the engine and the battery and arrows showing energy flow. Notice that the noise is probably worst when switching modes, and when coasting or braking the little regenerative motors seem to be arcing. Or maybe have somebody else watch the display and listen to the radio while you KEEP YOUR DAMN EYES ON THE ROAD! My 2005's noise is worst in weak(ish) or even not-so-weak AM stations. If something really is arcing it will generate electromagnetic interference (EMI) up into the FM band as well. Ask Marconi. Think "spark gap transmitter". An arcing brush in a motor is a very effective broadband noise generator.

It's damnably difficult to figure this out because it only happens while moving, such as just taking off or just about to come to a full stop. If I had a lift available I could put it up in the air and go around with a cheap transistor radio (do they still make those?), not a damned i-something, and hold it near the suspect parts. But somebody would have to be in the car, accelerating and braking and changing modes.

The dealer, who is not the jerkwad from whom I bought these two Prii and is not particularly dishonest (or at least hides it well), claims they know nothing at all about this but if I give them hundreds and hundreds of dollars they could maybe look around.

Toyota Customer Care doesn't answer e-mails. I shouldn't need to subscribe to a service just to get technical service bulletins (TSBs). Of course, as far as Toyota is concerned you are the ONLY Prius owner ever who has whined about radio noise.

And the noise itself isn't whining. That would be an alternator or a bad battery connection. It's not spark plug noise - why would you hear when the engine ain't running? It is definitely arcing in the controllers or motors or motor/generators and I haven't found it yet. I have not torn the headliner apart to check the mounting screws for the antenna.

Anybody had any success?

 

I think MG1 and 2 are actually immersed in ATF, and are inductive motors. No brushes. I can tell this is really bugging you. I like the part about sleuthing about with an off-station AM radio. I would do something like that. With an earphone hooked up though, while somebody else was driving so you can associate the radio noise with any AM static. I don't think you can successfully operate the vehicle up in the air unless all the wheels are turning. It will throw ABS and VSC codes. The next step I would take would be to acquire the electrical and signal schematics and look for any capacitive filters (called condensers back in the breaker-type ignition days) and then check these for shorts. With all the signals running around in that car there are bound to be a few filter capacitors. If you have fully diagnosed, to your satisfaction, all of the various grounding points, then I would proceed with the above. You say a change of battery and change in the weather brought it on. What kind of change in the weather? Dry to humid or the other way around could cause grounding points to act up. I wouldn't think that a new battery could cause anything, but maybe something is shorting inside the battery. Tough job ahead of you . Good luck.

 

"a faulty ground controlled by the throttle" ??
Say what ??

The most common cause of static and poor reception is a defect in the antenna circuit itself......the center conductor of the wire......or the "plated" antenna on the back window (if it has that kind).

And probably the most common of those faults is a bad connection AT the connection point for that "plated on the glass" antenna near the back window. Next probably would be damage to the plated "wire".