I recently bought a 2006 Lexus LX470 with less than 20K miles. The radio will not bring in my local NPR station WILL am and fm. After having a new dealer installed radio my reception is only slightly better. Other vehicles have no trouble receiving these stations. Any ideas?
Could there be a problem with the antenna or the antenna connection?
Does a new LX470, or whatever they are now, bring in the station? Ask the dealer to let you try one.
It sounds like the antenna is the problem since the radio has been replaced.
The antenna is fine. Could it be a software problem in the gps unit which displayes a number of functions including radio settings?
The trouble isn’t in the software. The trouble is with the RF signal level input to the tuner section of the radio. You have a new radio with only marginal improvement over the original unit so the trouble would seen to have to be with the signal input to the radio. Some newer vehicles have a RF preamp in the antenna circuit. I’m not sure if yours has one or not but I wouldn’t be surprised if it does have one. There may also be a tuning circuit for the antenna input in the radio but I’m not sure yours has one. Though that was used mainly for the AM band.
How do you know the antenna is OK? It sure sounds like the antenna. Just because some other stations come in fine, does not mean the antenna is OK. If one station does not come in well, it could be that it has low signal strength in your area and add a poor antenna and you get no reception.
Pay attention to cougar. He knows what he’s talking about. The GPS system software should have nothing to do with this. You say the antenna is fine. How do you know? Just because it isn’t visibly broken doesn’t mean it’s fine. There could be a bad connection at the base or the antenna wire could be broken or crushed. The pre-amp idea cougar mentioned is also a real possibility if your car has one. That could even be as simple as a blown fuse.
Thanks for all the responses. My dealer told me the antenna is OK. When I asked how he knew I was told that it either worked or did not work. Thinking about this I now believe that only local very powerful stations are being received in spite of the antenna not through it. I have requested a replacement antenna and hope that does the job. I will let all of you know the result. Thanks again.
From what you state it seems to prove to me also that the antenna is only partially working. The signal being picked up by an antenna system with a problem can still be getting through but with a lot of signal loss and radio will only be able to pick up the strong signals. Just what you say is going on. The service shop statement about an antenna either works or it doesn’t is absolutely wrong. The problem may be due to a bad antenna ground or a bad center pin coax connection.
I found some data for your vehicle but it wasn’t detailed enough to show the antenna input to the tuner. Since you have a GPS system also there may be a single antenna for both systems and some sort of RF network to seperate the signal bands. GPS signals are much higher in frequency than AM or FM band signals and require an antenna tuned to a much different frequency. There very well may be some sort of active antenna system between the antenna and the radio and the problem is there. If there is one it may be located in the roof area. Usually GPS antennas use some sort of active antenna system at least. Ask the service shop if there is some sort of antenna tuning network or RF amp between the radio and antenna.
The easiest way to verify that the radio input is ok is to connect a RF signal generator to the tuner input and check the signal threshold of the tuner. Is a automotive shop going to have one of those on hand…NOT. That would have to be done at a electronics service shop most likely.
Keep us posted on the progress and don’t let the service shop just pass you off by saying “they all do that”.
Thanks again everyone Cougar in particular. Lexus warranty has been very slow at getting back to me other than checking whether the new radio worked better - as you know it did not. In the meantime I have installed a high quality RF amplifier as suggested on this site. There is a significant improvement in FM reception at the same time AM reception, which was barely audible at best before, has now vanished on all stations. I am going to continue to insist on a new antenna and will let you all know how that affects reception. Thanks again to everyone.
Never believe everything a dealer says. 
Software…NO WAY. Software doesn’t control the frequency settings.
This is either a antenna problem or a bad ground.
Antenna amplifiers for cars are very often FM only, and while they should pass AM through unchanged it’s really impossible to add something in the path without some loss, and if your reception was marginal on AM to start with that might be all it took.
You are welcome for the help. I still suspect there is a amplifier in the antenna circuit that is causing this problem and not the antenna itself, though it could be the cause of the trouble.
I thought an update on repairs is in order. To date the entire radio system has been replaced to no effect. I have a new radio, antenna, coaxial cable connector as well as an additional RF amplifier in the vehicle. Radio reception on two channels I favor is still intermittent, poor or non-existent. Any further suggestion are welcome. The stations in question are clearly received on every other vehicle I have tried as well as on portable radios at home. Do I have to live with this weakness or is there anything else to be tried? Thanks in advance for all your help.
Since the dealer is unable to help, take the car to a sound system installation shop. They’ll have the radio working, as it should, in no time. You may even be able to charge it to the dealer, if it’s a warranty item.
How far away are the stations you’re trying to pick up???
It may be the radio itself…In so much as the design of the tuner section in this radio is NOT good. Does this car come with the Mark Levinson radio option??
Here is the latest on the radio saga. Yes the vehicle has a Mark Levinson sound system. No, there is no reliable sound system installation shop within a 100 mile radius. I could go to Chicago, St. Louis or Indianapolis if need be if I had a highly competent place to go to.
Finally, the other day as I exited a automatic car wash the radio came on by itself, activated the antenna and announced that FM radio was on. Two days later while backing out of my garage it did the same thing less the announcement. In both cases the radio picked up the PBS station just fine. Is it gremlins, a software glitch or ???. All responses are welcome and appreciated.
Since the trouble went away for a time at least, the trouble must be with a connection in the antenna circuit somewhere. It may just be the grounding to the car body at the antenna. If the dealer service would do their job it would be fixed.