Okay, so I've been having this recurring problem with my car that the sound doesn't work in my system (98 GS400 Nakamichi) from time to time, especially after it rains. I've had many people look at my system for errors, checked everywhere for leaks, moisture, blown fuses, mobile phone wiring, etc. and have come up empty...

Well, I met with yet another mechanic today and he told me that he's almost 100% it's some defect with my head unit in my 98 GS400 (Nakamichi). He didn't think it was my amp, either.

I went to my local Lexus dealer and they told me the warranty for the radio was 4 year/50K miles, so I'm out of luck there.

Here come the questions:
1. Should I get a new head unit, subwoofer, and amp for subwoofer (only these three things)?
2. Should I try to replace the head unit and Nakamichi amp and stay stock?

Thanks for your help!

 

When you say "no sound" is the radio on but you don't hear anything from the speakers, or does it completely lose power? Any popping, crackling from the speakers? Any popping, crackling when you adjust the volume?

 

Pianoman, my "no sound" really means absolutely zero sound all the way up to maximum volume. There is no crackling whatsoever. My radio (or at least my sound) has not worked for the past few days straight now.

The one time it DID work this week, the volume came on, but it sounded like it was struggling to stay "on". It sounded like the volume was at 50% and then 70%....the sub kinda' kicked in, but not really. I think in the end, it stayed on at about 80% of its usual quality.

Could this be the amp? Faulty headunit? Wires just need to be unplugged and then replugged?

I don't know what to do...

 

Sounds like the amp isn't getting power (bad connection) or is faulty. You could see if a general electronics shop could run some tests on it for you before you start buying new stuff. Amps all follow the same basic design.

 

Yeah, I might have to drop by a shop to get it checked out, but I'm not familiar with anyone that I trust in the area. Who knows, they could cut a wire and tell me I need a whole new system, you know what I mean?

BUT, tell me what ya'll think about this...

Today, I took out the glovebox to poke around a bit to see if I could find any condensation (even though I did that before and didn't find any). While looking, I saw the cut wires of the old mobile phone that was attached to it when I first bought the car. My buddy cut the wire and tucked it in (un-taped) the carpeting on the driver's side.

When I saw that it was exposed, I saw the "orange" wire which someone told me in another thread that this was the MUTE wire. So I immediately taped it up and tied it to another wire to keep it from moving. So far, my radio has been working today. Could this have been the culprit all along?

Another reason that I think this is suspect is that sometimes (after this problem started happening) I pointed my cell phone towards the radio and got some static. Could that have been interference from those mobile phone wires? I'm sure that it's still plugged in the back of my HU as I've never opened up the main dash to take out the HU.

This wire was cut the first month of my buying the car back in 2002. The thing is, the loss of audio never happened in my 2 1/2 years of owning the car until this past summer.

Sorry this was so long. It's so hard to explain in just a few sentences! Thanks for any input on this!

 

GOOD CATCH!!! I bet you are right. The mute wire just mutes all the speakers. Tell your friend to not do such a sloppy job next time. lol

 

Thanks for the encouragement! It's been really frustrating for me...

Should I just go for the whole shebang, take out the headunit, hunt down the wire, and pull it out?

I just don't understand why it took THIS long for the mute wire to start kicking in (if this IS indeed the culprit)...

Any thoughts?

 

If your car is wired the same way as mine, the headunit receives the must signal from the telephone relay and it passes this mute signal - in a seperate wire - on to the amp. Disconnecting the mute wire from the HU like you suggested should stop the problem at its source. The mute wire might be getting grounded somehow - being loose.

Easiest way would be to put some electrical tape over the pin in the connector that plugs into the back of the HU. I don't have the diagram so I can't be sure the color is ORANGE but you can always call the dealer to confirm. Ask them to look at the stereo wiring diagram for your NAK system and tell you what color the MUTE wire is that connects to the HU from the telephone relay. Or the diagram might be here in the forums somewhere.

If that doesn't work I would then disable the mute wire that runs to the amp from the HU.

 

Yeap, I thought I fixed this problem until it stopped working AGAIN. I've got to say that this is really frustrating to me. I want to switch out the H/U so bad, but if this muting is due to the mute wire and I try to use the factory wiring for my aftermarket H/U, then I'm gonna have the same problem. I just want some music, is that too much to ask?!

Anyway, I think this is the wiring diagram for the Nak systems. Can anyone confirm this? And, should I pull and tape ONLY the Telephone Mute wire or should I also pull the Mute wire as well?

 

Here's another diagram for the GS, but I don't recognize it. Maybe it's the diagram for non-Nak systems?

 

Bump for desparation...

 

Have you traced the cut wires of your disconnected phone kit to their source so that you can disconnect (and completely remove) them where they connect to your audio system? Maybe there is more than one point of failure along this wire where it is being grounded.

Based on the orange mute wire, the disconnected phone kit might have been a Motorola. It must have been an after market phone since the OEM one would have plugged into the cars OEM phone connectors on the wiring harness.

It may not matter since I have an LS, but I think I have verified that, for the 2000 model year LS, telephone mute was accomplished at the HU for Nakamichi but at the amp for standard Pioneer and Nav. It was easier (and safer) for me to attach the phone mute wire for my Nokia kit to the mute pin in the OEM phone connector under the center console rather than mess with the head unit itself.

I read recently that cell phone antennas can cause interference when near the head unit of a radio. Then I read that my Nokia car kit phone cradle (which is mounted next to my 00 LS Nakamichi head unit) automatically deactivates the phone's internal antenna when the phone is inserted into the cradle to prevent interference with the radio. When in the cradle, my phone uses the OEM phone antenna imprinted on the rear window.