Radio static

Nothing exactly easy I can think of, but the connections at the antenna and the back of the headunit should be checked.

AM stations are very suceptible to static, due to the ionospheric bounce they rely on, but FM signals are very LOS (line of sight). If you are trying to pick up a station who's transmitter is behind a hill or large building from you, you'll get a poor signal. So, consider your geography, especially if you live in a city near tall buildings or hilly country.

Has your antenna been damaged by a car wash, maybe?

I've noticed some stations come in better than others, but I'd say the Prius has a less sensitive antenna than other cars I've owned.

 

There is another thread on this topic and the problem seems to be isolated to some, but not all Prii. Once it starts it gets progressively worse. I just had my whole radio unit replaced under warrantee and the problem completely cleared up. BTW I have an '04 'premium' system w/6 CD changer.

 

Hmm. I just started getting more static in the mornings when I listen to a DC station on my way from Mount Airy (Frederick area) to Baltimore. I assumed that it was the crappy atmospherics we have been having for the past few months. The air is so thick with humidity and smog you can almost cut it. I guess I need to keep an eye out to see if it gets worse.

 

It took my bringing it in to let them hear the problem. Then they jiggled something and said it was fixed. By the time I got home it was as bad as ever so I called and raised hell. Right then, over the phone they asked me to get the part number off the radio and they ordered a new one. Was replaced within a week or 2.

 

I have static in my AM radio too. I have a 2005 Prius (Gen II) does a head unit with Aux for iPod fit my older prius.....??

 

Well thats not quite right right, the AM stations are more susceptible due to the fact that AM relies on AMPLITUDE MODULATION. Static is just a LARGE amplitude pulse of sudden noise and the AM section just deals with it as more signal. Thats why it sounds louder on AM.

FM, or Frequency Modulation depends on the modulated frequency of the center carrier frequency and is NOT amplitude dependent. What that boils down to is the circuit clips the static to no more the amplitude of the FM signal. While you still hear static, it is not the crashing sound you get on AM.

There is a pre-amp in the base of the antenna and if that has gone south, you would get weak signal, and possibly more noise. If you replaced the whip with a sharkfin or smaller antenna, you will receive less of the signal you want. If the static source is close to you, the more of it you woulod hear compared with the signal you want.

If the ground of the antenna coax is broken, that might let in more of the internal noise that the Prius generates into the radio, or the antenna plug just might be loose and have to be reseated.

Good Luck 73 de Pat KK6PD

 

Is there anyway to diagnose what part of the system might be causing problems?

I've just finished rigging my carputer so it plays nice with the radio and such and I've noticed my FM stations have a very small but constant amount of static (not related to car vibrations, amplifier effects or the like - CDs, computer audio and AM all work fine).

Now given my poking around the dash I'm willing to bet I may have knocked something loose, but I've checked the Motorola plug and it seems solidly seated (and AM performs well so no problems there I guess). Can I electrically test for a broken ground or similar somehow?

 

Might be a problem with your ground. Have it checked by an electrician or an audio expert.