treehan77

1) which vendor on eBay did you use?
2) I have no sound, and no control of a/c functions. Ie can’t switch from auto, fan speed etc. I also no longer see the temp it is set to in the little LCD display above the screen. Do you have these same symptoms? Thanks

CA2WALS430

@treehan77 , yikes, no, my symptoms are only no sound and my nav buttons don't beep, but I have full functionality otherwise. The solder issue could apply to you also though; these cars were notorious for them. Like Big Boomer said, those were the first years they took the lead out of the solder, and they had not found an additive yet to make it flex.
For my amp I bought from OEMAutoAudio. Like I mentioned, 100% good reviews with many sold, and they pay for return shipping. For my NAV unit, 3 years ago I sent it to a place in California and that is all detailed in this thread:
https://www.clublexus.com/forums/ls-...connected.html
I imagine you could take it to several places, but as Big Boomer will tell, it needs to be someone who knows solder techniques.

alextv

You can tap on the unit with plastic or wood end of screwdriver to see if bad joints and if so what I used was a slender plastic coil tuning tool to run over parts quickly to pinpoint bad joint. If bad joint this will most of the time find the joint but one thing to mention is that a chip can have a bad joint in it also. To verify if chip I would isolate the chip and use freeze spray. An experienced repair shop will already know suspected areas or bad parts to complete repair. I have seen joints that look bad be good and vice versa. The design of any system has its weakest points that are common and once a technician knows that it is what is looked for with every repair.

CA2WALS430

Tah-dah! I did it! I am rather proud of myself when I pull these things off. This Saturday I will mail off the core for my $125 credit towards the bill. Everything works like a dream. I test drove the car, started and stopped the car and turned the audio on and off 10 times or more and all is back to normal. Thank you again for any input you offered, espcially @BigBoomer and @alextv , and of course thank you to https://www.oemautoaudio.com/, whom I found on eBay, for refurbishing these and running this easy exchange program.
I also used and offered thanks on this thread:
https://www.clublexus.com/forums/ls-...-and-pics.html

Beware those little 8mm hex bolts that hold the amp braces on are a little soft. I shredded one by hand, no power, and had to have someone drill it out. Then I couldn't find any Lexus or Toyota dealer that had the screw, 90153-50010, in stock, so I ended up at a nut and bolt company. He wasn't super thrilled about helping me for a $1.00 purchase, but nevertheless, he came through and all is well.

****Also, for whomever reads this in the future, YES, for whatever reason, the beeping of the buttons on your nav unit is wired through the amp, so it gets fixed at the same time. Confirmed through several tests; every time the stereo came on, the buttons beeped; every time the sound went out, the buttons didn't beep.