Prius AM Radio

[DonGoodrum]

I have a 2005 Prius, package 6. The radio has given me problems from the start, replaced once, and is defective again. The AM portion which is all I use only operates normally about 5% of the time. The rest of the time it is so full of static it is unusable. The tech at my dealer told me that it coud not be fixed (still in warranty).

I believ there is a bad connection in the system. FM, disc, and tape operate normally. Even using the brake generates noise on AM. Would appreciate any comment on this problem. Essentially I don't have a radio.

Thanks, DonG

[bredekamp]

Originally Posted by DonGoodrum

I have a 2005 Prius, package 6. The radio has given me problems from the start, replaced once, and is defective again. The AM portion which is all I use only operates normally about 5% of the time. The rest of the time it is so full of static it is unusable. The tech at my dealer told me that it coud not be fixed (still in warranty).

I believ there is a bad connection in the system. FM, disc, and tape operate normally. Even using the brake generates noise on AM. Would appreciate any comment on this problem. Essentially I don't have a radio.

Thanks, DonG

Please provide more info. You say the entire radio unit has been replaced already? It still does it? Then you're looking at a problem with the power supply to the unit or the antenna being wonky. If noise was entering the system somewhere the FM would work normally cause FM radio can reject noise.

Does anybody know where the AM antenna would be or whether it uses a ferrite core coil antenna inside the head unit? The FM antenna is the little beesting on the roof. The AM antenna should be a long loop of wire.

What does the static sound like? Constant hiss/swoosh = weak signal
Clicking or ticking = electrical noise/spark ignition
Buzzing = interference from electrical wires 60/50Hz hum
Hum that changes in pitch as you drive/brake = Inverter switching noise

Perhaps try a filter on the power supply to the radio head unit. If the head unit has an AM antenna input, try sticking a long wire in there and see if you're reception picks up.

[bredekamp]

Also check:

Soultek.com: Toyota Prius hybrid car radio problems?

It looks like a common problem.

[DonGoodrum]

The noise is a mishmash. Evidently the electrical system it self is partly to blame as evidenced by the static from the brakes. The fact that at some time it stops only adds to the confusion.

The ignition does not appear to be the culprit. I am familiar with ignition static from using ham radios in the past. My problem is with the dealer trying to make it sound normal. Thanks for the input.

DonG

[bredekamp]

It is certainly not normal. My final word:

Something isn't grounded to the chassis somewhere. This could be hard to find.

[NoMoShocks]

If under warrantee, go to techs at other dealers to get it fixed. I think the AM and FM antenna should be the same peice on the back of the roof. Maybe the shield on outside of antenna cable is not connected properly. I don't think I have listened to my AM radio for more than a couple seconds at a time when going through the modes to get from FM to CD or back. I think I better listen to it for an exended time and make sure it is working ok.

[tochatihu]

You may or may not be willing to chase down a bad ground somewhere in the system, but when the Prius AM radio is working correctly it is pretty darn good.

I have done a lot of AM DXing to pass the time on late night drives. The antenna is indeed the stick on the roof. The shielding and isolation are indeed impressive, because any other HF radio in there will only hear the Prius' electrical system, up to about 26 MhZ.

[bredekamp]

Originally Posted by tochatihu

You may or may not be willing to chase down a bad ground somewhere in the system, but when the Prius AM radio is working correctly it is pretty darn good.

I have done a lot of AM DXing to pass the time on late night drives. The antenna is indeed the stick on the roof. The shielding and isolation are indeed impressive, because any other HF radio in there will only hear the Prius' electrical system, up to about 26 MhZ.

I agree, I listen to AM all the time and the sound on my 2006 is as good as AM gets. The only buzzing I get is when I drive under power lines. AMs' inability to reject noise is why we switched to FM in the first place. Perhaps it's time for digital AM radio to take off.

[MrK(2)]

Originally Posted by DonGoodrum

I have a 2005 Prius, package 6. The radio has given me problems from the start, replaced once, and is defective again. The AM portion which is all I use only operates normally about 5% of the time. The rest of the time it is so full of static it is unusable. The tech at my dealer told me that it coud not be fixed (still in warranty).

DonG

Sometime, when you're at the dealership, why not park beside another Prius for which the service department would have access to the keys. Ask them to tune both your radio and the other Prius' radio to the same AM station. See if both have the same interferences.

If not, tell them to figure out the problem and fix your radio.

[bredekamp]

Originally Posted by MrK(2)

Sometime, when you're at the dealership, why not park beside another Prius for which the service department would have access to the keys. Ask them to tune both your radio and the other Prius' radio to the same AM station. See if both have the same interferences.

If not, tell them to figure out the problem and fix your radio.

Good idea. Do that. Compare it to something you KNOW works. Then they can't explain it away as being solar flares or some other sh!t.