Whitmanpc1

In my 93 SC400, the Nakamichi radio has NEVER had good AM reception. FM is great, but no AM.

Has anyone had this problem? What could it be? Lexus looked at it 2 years ago and didn't really have an answer!

Thanks!

CmputerWiz

Are there really AM stations still out there? Well I know radio waves somewhat well....and a car antenna is not a good receptor of AM at all. AM really needs a loop, not a monopole. The back of that stereo has two inputs for antennae, but they both run back to the power antenna. You could always get an extension, and run the small one of the two over to an AM loop antenna and mount that like under the rear deck or something.

Just an idea.

SR

Whitmanpc1

Thanks! When I stop by the Lexus service station I'll talk to them about that. If I ask nicely enough maybe they'll tell me how to take out the radio!!

CmputerWiz

Well doing this shouldn't require removal of the stereo. If you open your trunk, and remove the liner on the side where the power antenna is, you should see the thick black cable that goes into the power unit. It's two black cables hooked together. I think they just disconnect somewhere right there...i'll hafta look in my trunk again. You could disconnect the small one of the two right there, get an extension from Wal-Mart or wherever, and at the end loop a copper wire from the center post of the wire to the outside metal part of the antenna.

Sounds confusing, but I'll post a digital pic of what I mean within a couple days.



SR

DickLexus

Have the Lexus dealer check the Technical Service Bulletins from 92-93. I recall seeing one addressing poor/weak am reception. Can't remember what the cure was though.

****

Whitmanpc1

Thanks SR!!! I look forward to seeing the picture and really appreciate you going through the trouble. I hope this fixes it...I need to listen to my Red Sox on AM!!!

Whitmanpc1

Hello all!

I went to radio shack and purchased an AM loop antenna. I pulled the connection off the car's antenna and just touched the wires on the AM loop to the inside of the wire...and AM came in!

The problem: it came in great when the AM loop was on TOP of the car, but when I put it in the trunk and closed it, nothing again!

I've seen some auctions on eBay for a power antenna and am thinking of getting one just to see if that clears it up.

Anyone have any input on this? I need my AM for news and Red Sox!!!

Thanks for everyone's help!

MrWigggles

I am in the process of purchasing a 95 SC300 and it has the same problem with AM reception on the NAK deck. FM is great.

I don't know what the solution is as of yet, but I wanted to let you know there are more latter model cars that have the same problem.

-Mr. Wigggles

Whitmanpc1

FINALLY...like pulling teeth, I got the Lexus dealership to check out technical bulletins for weak AM reception. They found one!!

I'm attaching the eFax they sent me. I'm not sure if you can view it, but very interesting reading. If your AM reception is not as good as it used to be, this will fix it.

By the way, I now have strong AM reception. Installed an aftermarket antenna and it works great!

Jeff

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MrWigggles

Thanks for the info.

Could you tell me what aftermarket antenna you went with?

-Mr. Wigggles

Whitmanpc1

Check out this eBay link. This is who I purchased my antenna from and this one is the same brand as the one I purchased (Metra).

Warning: Although it cost me $45 for the antenna and $80 for the install (and the factory one from Lex costs $299), I would advise against this non-OEM antenna.

The installation was EXTREMELY complex and took the shop (very competent) over 5 hours to install it. According to that, it should have cost over $300 in labor to get it in. They didn't charge me that because they charged me for the time it SHOULD have taken.

It's working perfectly fine now and I have crystal clear AM & FM, but they jumped through hoops to make it work. I'm not an electrical engineer, but I stood there listening to them and watching them do the install. Lexus has atypical "pin out" configurations on their antenna and they had to install/fabricate several "things" to make it work. I'm adlibing here, but something about capacitors, jumpers, things to trigger other things... "Things" equals technical terms I can't remember but I do understand.

They mapped out on paper all the wires and that took them almost 1 hour! Once that was done (about 4 hours into the install) they finally had a quantifiable path to getting it done. All the time before that was wasted in a failed "trial and error" session.

My advice would be to bring the car to a car audio specialist with the technical bulletins I posted. The problems seem to be in corrosion and the procedures show how to fix it.

If my Lexus dealer had known about this technical bulleting it would have saved me the past 4 years (on and off) of trying to figure this damn thing out!

Go Red Sox...I can listed to the games in my car now!