Just when I think I've got the conditions figured out for when this issue occurs something else happens to mess it all up.
I got in the car this morning and it was colder last night than it had been in a week or two, started the car and the radio took about 10 seconds to come on, so the problem also exists when it's cold.
In light of this I think I am more or less convinced that the amp is the issue, probably just a cold solder joint or something, although the disappearing buttons under audio concern me, but not knowing the internal design or what exactly each wire going into the amp does I can't say that it will or won't cause those buttons to disappear.
The mute wires have no effect on the issue and from what Jainla said it didn't change the buttons available either, I used the pdf from earlier in this post from 1990LS400 to figure out and disable each mute wire going to the amp with no improvement, the amp connections are correct on the diagram, just match the colors and pin count to figure out which connector it is, it is not top to bottom like the diagram.
I have verified that the hot at all times is in fact hot at all times and I also verified that the ACC is hot with the ignition in ACC, or On. So either a signal isn't getting to the amp from the player up front or the tuner in the rear or there is just an intermittent connection that is somewhat temperature sensitive inside the amplifier.
Also, thinking from the perspective of a Dealer and what they would do, I know the first thing they would say/do is replace the Amp so unless someone else has any feedback or ideas, I'm going to replace the Amp, cross my fingers, and hope that it fixes it.
Hey did buying the new/used amp ever fix your issue? I have the same problem on my 01 UL. The radio doesn't come on at all, then with the radio off the speakers start making an annoying sound that sometimes gets very loud. It's like a scratching noise that may actually damage my speakers. Please let me know if that actually fixed the problem because there's only one guy on eBay who's selling this amp and he wants $900. Just wanna know if that's the only way out. Hope not but would help to know. Thanks in advance.
No Audio At All - 01 Ls430 Ultra With Mark Levinson
in 01 - 06 Lexus LS430
Posted
Hey did buying the new/used amp ever fix your issue? I have the same problem on my 01 UL. The radio doesn't come on at all, then with the radio off the speakers start making an annoying sound that sometimes gets very loud. It's like a scratching noise that may actually damage my speakers. Please let me know if that actually fixed the problem because there's only one guy on eBay who's selling this amp and he wants $900. Just wanna know if that's the only way out. Hope not but would help to know. Thanks in advance.