Question Intermittent audio while car is moving.

[ImWolf]

Strange issue first noticed yesterday with my (Toyota) JBL audio system. Started the vehicle and radio comes on which is set to an FM station and it sounds normal. I put it in reverse and back up about 30 feet, and suddenly it sounds like broken up reception from that station. Very rapid "machine gun" of intermittent sound, but I can still recognize the song. When the car stops moving, the sound returns to normal.

So I put it in drive and proceed to my front gate, and again it sounds like the bad reception while I'm slowly driving forward. I change the channel and find it's not the station because other channels are also delivering intermittent sound. When I stop the car again at the gate, sound returns to normal.

This pattern continued as I went down the street. Eventually I switched to the CD player and heard the same crappy sound while the car was moving, but clear normal sound while the car was stopped.

Later when I was stopped, I put the car in park and hit the gas several times revving the engine and the stereo sounded normal. As soon as I start moving again, even 2 or 3 MPH on a smooth road the intermittent broken up sound kicks right in.

Does anyone have some diagnostic techniques to suggest that hopefully don't include dismantling door panels or removing the stereo from the dash?

Thanks,
Wolf

 

[helpstar]

Which Toyota model is it (including manufacturing date) or which exact JBL system is it?
Might be a loose cable or similar. Try removing the radio and check connections behind
check if any fuses are corroded or not well

 

[ImWolf]

The vehicle is a 2008 Toyota Rav4 Limited. None of the documentation or identification on the stereo help with determining exactly which system this is, but it’s the Premium JBL system that was an option with this car.

After my original post I played with it some more. First I just tried slamming doors to see if that made a change, which didn’t happen. I also checked the fuses and found no problems.

While I was doing this I noticed something which I had not before. As the car started rolling slowly, the intermittent sound was also slow, and then it became more rapid as the car rolled faster. This is just moving forward or reverse without constantly having my foot on the accelerator.

The next day I wanted to take the car to a hill for further diagnosing. I wanted to roll down the hill with the engine off to see if the audio would again be broken up. That was a few days ago, and when I started off the stereo audio somehow fixed itself and has been normal ever since. (I hate intermittent audio, and I hate intermittent problems!)

I’m assuming the issue will crop up again at some point.

 

[helpstar]

probably a ground issue / connection problem

check the connections behind the radio
maybe this could help as well
https://www.crutchfield.com/S-VZQOe...car/noise_suppressors_installation_guide.html