thholr

So today for the first time in 107k miles I have had a really strange audio issue. I start the car in the morning, radio comes on but no sound. I can change stations, everything works but no sound. Even clicks on the nav screen dont produce sound. I turn the car off at the gas station , same thing. Drive to work. After the gym I go to start the car everything is fine. On my way home I started the car to no sound, turned it off and on and it is fine again. Any idea what this might be ? I wonder if a fuse to the amp is going back , or maybe even the amp. I didnt have any tools with me so cant check for amperage at the amp. I have not located the amp yet, I do have the mark levinson audio system. I assume it is hidden in the trunk somewhere.
Other things to check ?

LifeSimple

When this happens again, play with the sound output and isolate each speaker by moving all audio to LF speaker, then RF, etc. If sound comes on after you've narrowed a speaker out of the equation, that speaker is most likely shorted causing the amp to "mute". See if that helps and report back.

YaMomma

Amp is in the trunk on the right hand side under the jack tools. You may want to also check and make sure you don't have water in the compartment where the amp lives. How water gets in there i have no idea, I've never endured that problem but there are a few posts related to it.

Majic24

I have the same issue. I sent my amplifier to Mark Levinson authorized repair in N.Y. They did a factory stress test on the ampbut could not find any faults etc. Never a drop of water in the trunk. The only thing I notice is if I don’t drive the car for 3-5 daysno sound happens. When I drive the car everyday no sound problem doesn’t happen often. The tech at M.L. told me these amplifiers have intermittent problems. $750 exchange program with no guarantee to be a sure fix.

CottageChz

Check the trunk for water as others have said. I had my amp fried by water in the trunk, same symptoms as what you are describing. Audio worked a little bit sometimes, most of the time not at all. Radio screen functioned as normal. Hopefully you have a different issue, but you definitely need to check your trunk for water when trying to diagnose. If you search through my past posts or search the forums for "water in trunk" or something like that, you'll find 2-3 threads on the issue.

Edit: I said the radio screen functioned as normal. I forgot, I am pretty sure the volume was stuck at 20 or something. Everything else worked as normal, but I think the volume was stuck at a certain value and couldn't be adjusted up or down with the **** or the steering wheel controls.

Majic24

CottageChz
I mentioned in my post that I have never seen a drop of water in the trunk and no signs of moisture/rust etc. Additionally the amplifier was checked by Mark Levinson and found no evidence of moisture/water. Head unit functions perfectly, M.L. tech said they almost never see the head units in for repair. I believe he said the head units were manufactured by Panasonic.

In my discussions with the tech he made it abundantly clear that these amplifiers have had issues with intermittent operation. And most likely that’s the cause. But would not guarantee that with replacing the amp it would solve the problem at my $750 expense. I am actively speaking with the tech about this. And now that another C.L. member has same issue, I will advise him and see if we can escalate this.

CottageChz

Yeah, I know you said no water, just wanted to make sure the OP checked all possibilities. I also have only the base amp and not ML like you and OP, so it's a very good chance OP has same problem as you, and not the problem I have. Just wanted to share my experience since maybe it would be helpful.

thholr

Thanks for all the feedback. I just checked the compartment and it is bone dry. No signs of there ever being water. I think I may be having the same issue Majic24. About 4 months ago I bought a mustang convertible since I was wanting something with a big V8 in it and no roof. So now I drive the lexus 2-3 times a week, but at times it sits there for 3-4 days. Just weird I have never had that before. Since I drove it that day it has not happened again. I will keep monitoring it . If it happens again, I will check amperage and test each speaker to see if I can isolate something. Appreciate all the help.

Majic24

thholr
Please keep us updated. I will be contacting my tech person at Mark Levinson and advise of your situation which appears to be the same as what I’m experiencing.

4INSONLY

Hey everyone I know this thread is old but I am having the same issue. I sent the amp to United Audio and they said there is nothing wrong with it. Reinstalled checked everything. No water. Fuses fine. Checked the vents they seem to be in good order and car wasnt being drove and in the garage and I played music for a few minutes got the pop and sound went out. I turned off the car and it came back on. What else code it possibly be? I do see there was a B15 error code with previous owner back in April/ If anyone knows anything other than spending 1500 at dealer that would be greatly appreciated.

GSJ350

Just going off the *POP* noise and then you have to reset the system to come back on, makes me think a short in the wires are creating a spike in the system which puts it into a safety mode. Have your door panels or anything of the sort ever been removed? When this "POP" occurs is the base really "Hittin" or the vehicle moving and shaking? Are there any patterns you've noticed?

4INSONLY

I would say in the couple hours since I reinstalled AMP the only thing I can think of was that I had the radio super loud.

GSJ350

Ok well that's something at least to start at 👍🏻. So when the volume is at the upper level of it's available range, one would assume that max wattage or draw on the system would occur. Amplifiers electric motors electric heaters and pretty much anything else that uses electricity will always pull the amount of power it needs until the system limits out. The limiting factor could be wire size or guage... conductivity of said wire... Or bottle necks in the path of flow. So if your battery terminals have some corrosion or a fuse has some corrosion to which even a ground being corroded and maybe becoming loose. I'm thinking this through as I'm writing this if it seems a little odd😜. So I'll start with; Are you in the North East? When the music is pretty loud is the base slammin? (Which will draw the highest amperage). Check your battery terminals along with all radio fuses and their prong's to see if corrosion is present creating resistance and make sure all the grounds coming from your engine and body harness which start in the engine bay and may run partially down the lower frame rails toward the back look tight and clean. I'm a technician on the side and as a hobby so these things get my problem solving side working 👍🏻. Let me know if you find anything.

4INSONLY

No, I am not in the North East but I do tend to listen to a lot of bass heavy music and the song that was on was hitting pretty hard. I just checked the 30A Amp fuses and they both read fine. Battery terminals are clean. So I guess I will have to check the grounds after work. I will see if I notice any significant changes during my commute to and from work today. I really appreciate your input!!!

Nalod

Music “Popped” but it never came back on?
What year is the car?
Are speakers ML “Stock”, no changes? ML lexus woofer is still in place?
Cleaned power connections? Cables and connectors can corrode a bit.

Shame the link from two years ago was not updated with the results as promised by some.
If your keeping the bass way up and at high volume it can tax the amp. But if it checks out fine and no fuse is blown, then vibrations and the connectors could be issue?
If you find a fix please pass it along. Good luck!!