2004 Prius and I have lots of static in the AM radio. Some days it is worse than others mostly I am unable to listen to it. If the car is in accessory, the static in the AM radio is not there. As I drive the car the static will increase or decrease based on the proximity to the overhead wires. There are days however where the static will be hardly noticeable. I've owned the car since 2006 and have always had this issue.
Well welcome to the world of Amplitude Modulation. A system of radio transmission where the peak sound heard is the loudest and closest to the antenna! Since you are basically driving a 4 wheel square wave and harmonics generator, that's strike 1 against you. Those Noise spikes your are produces are going to be heard on the AM! Strike 2, as you drive along you are subject to any sort of amplitude interference you pass, noisy power lines, diathermy machines, though those are not as common as they used to be, lightning, big time! As you say, you have had this since the beginning. It's not the radio, it's the mode of transmission! That's why FM gained popularity in cars as fast as it did!
you may find it better or worse with a shorter or longer antenna mast. See Weak FM radio reception in 2010 Prius? | PriusChat as the threads for the antenna and basic concepts apply to both the Gen II and Gen III. The only difference is the majority of Gen II Prius have a 16" mast and most Gen III Prius have a 6" mast. I replaced my 16" with a 4" (see cheap shorty antenna that works | PriusChat) but I don't listen to AM.
Just a hunch, try unscrewing and tightening the little antenna on the roof. Or maybe remove and check for corrosion.
I don't doubt the poor AM reception reports I see here. Many of the reports come from people that know the difference, such as KK6PD. However, my 2010 GenIII Level 2 that came with the standard el cheapo radio performs admirably on AM and FM and has done so with stock radio and with the aftermarket Rosen Nav/Radio I replaced it with. I frequently listen to a 50kw AM station that is 100 air miles away and 5kw station that is about 90 miles away. The 50kw is solid any time of day or night except when the skywave and ground wave interfere sometimes at night and cause phase fading. The 5kw isn't particularly strong but is completely listenable as a talk station. My other tests are TIS stations on 530AM. They are 10 Watt Traffic Information Stations. One of them is 10 miles away (City oif Roseville) and completely intelligible while driving, another on the same frequency is about 15 miles away (Beale AFB) and can be understood while driving but the volume is very low because the closer one drives the AGC volume down. There is a 3rd one 25 or 3o miles away (SMF) that can occasionally be heard well enough in the background to identify it. I suspect the antenna that came on my car is one of the better ones that Toyota put on Prii. I doubt that all the noise sources in the car are appreciably better shielded than other Prii or that I happened to get two exceptional radios in a row.
Many major metro areas are out of FM spectrum space and AM works fine for talk radio. AM radio also works better for distant reception and when the line of sight path is severely blocked.
Thanks for the info on AM radio. I do recall stat-icky radio reception back when I was a kid but don't expect it today. My wife's 2010 Prius has nice AM reception.
I unscrewed and checked for corrosion and other issues. Seems to have helped. See what happens in the next few days. Thanks for ideas on how to fix!
Thanks for your detailed information with your gen 3. My wife has a 2010 and her radio AM reception is static free for stations that are close in proximity. I did a quick inspection of my antenna and by removing it and reinstalling it seems to have helped. Thanks!
BINGO! That trick helped. I had AM reception and it just got bad. This was after I buffed the car. I guess the buffer loosened the antenna? Anyway, Didnt have corrosion, just loose. I added some anti-ox conductive grease (bought at Lowes electrical department, just to seal that connection better and get just a tad bit more conduction. Thanks a million. I live and die by talk radio.
