DJKnetic

My 2007 LS 460 just started having an issue with the ML stereo where the sound will not work most of the time. 75% of the time when I start the car, the radio has no sound (no clicks, screeches, or anything, just no sound) and no visual response to changing the volume. When looking at the audio controls, the sound is set to the far right and rear. 25% of the time the audio works normally.

Looking through various threads it seem like it may be the amp going bad, but is there a way to test that for sure before sending my amp off to get repaired? I'm just surprised that sometimes it works just fine, and find it odd that it never suddenly cuts out when working at start up, or never turns on if not working at start up. But mostly I hate playing the game of "Will I be listening to music through my phone speaker or through the car speakers?"

I'm guessing the first step is to try to run the System Check Mode?

DJKnetic

I ran the System Check Mode and am getting NCON for DSP-AMP. Hoping I can get a chance to run it when the volume actually works to see what it says.

roadfrog

NCON means No Connection, the diagnostic code is normally P440 (from what I found online). I would check the connection to the amp first, and if all is good there, I'd be comfortable sending in the amp for repair.

DJKnetic

The stereo finally decided to come on. I did the diagnostic and everything read as OK. So it wasn’t throwing any code if I understand this correctly since it would probably say Check to view the previous codes. I will check the connections and see if I can find anything.

DJKnetic

I checked the connections into the amp and everything felt nice and tight.

Any audio people out there have an idea on why it would randomly have connection issues like that if the amp is in need of repair? It just seems weird to me that when it does work it never has an issue no matter how long the car is on. I've had aftermarket amps in the past that have gone bad that will work until they overheat and then cut out, but having trouble wrapping my head around the idea that it is all or nothing each time.

PandaAllan

Did you ever get this fixed? I know it was a while ago but I have been fighting with this same problem. Do I just need a new amp?

DJKnetic

I am still not sure how the amp would sometimes work, but I found with the cost of the replacement it wasn’t much more to just go with after market parts since I didn’t trust a factory amp to last.

Higgie

Are the buttons on the steering wheel working? If so try my fix in the link below. Probably just a loose soldering-contact.

https://www.clublexus.com/forums/ls-...-volume-2.html

PandaAllan

I believe all the buttons are working. With this problem though it’s kind of hard to check. I think I’ll just break down and by an amp. Did you find a decent aftermarket bolt on amp for under $200 because I don’t need anything special in that car it’s just a grocery getter.