gemineye

Hello all,

I recently purchased a 2015 GS F-sport, and noticed there is a cord that is plugged into the AUX input, and then it immediately runs underneath the trim. Does anyone know what this cord might be for? Also, I'm not sure what the stock setup is supposed to look like for USB and AUX inputs, or if the stock setup has 3 USB ports like mine does (2 USB and 1 AUX on 1 "block" and 1 USB input within a circular black housing - see pic). I wouldn't think so.

Lastly, I'm currently troubleshooting the audio system. When I first purchased the car, the stereo worked just fine; however, just 2 days later.....and I'm not getting any audio out the speakers. Sometimes the audio works; most of the time it doesn't. I did a ton of research here on CL, and I'm not convinced it's the Mark Levinson amp that is at fault. When I adjust the volume using head unit **** or steering wheel control, I can see on the screen the system is receiving that volume adjustment up/down; however, there is no sound. I removed the AMP, and it looks brand new inside, and there is no moisture inside the amp or inside the little "cubby" that it sits in. It looks brand new on the inside; and no signs of corrosion (see pics). I checked the fuses and all are good. Any help is much appreciated. Thanks.

EAST

Just out of curiosity, have you already disconnected the Aux cable? Volume issue is there with BT and radio (different audio sources)?

I'd say go ahead and take apart your center console to trace where those wires are going. It looks like the prior owner had some audio modifications which may help point to your issues. At least for the 4.5 GS (post facelift), it's two 10 mm, and removing some trim that's clipped in.

If I had to take a completely random guess, I'd guess that USB is either constant on (on when ignition is not on), or just something that provides more amps than the standard one.

gemineye

EAST: I disconnected the Aux cable, and it had no effect on the "no sound" issue. When the sound is working, it works on all audio sources (BT, FM/AM radio, etc.). However, when the sound is not working, it doesn't work on any of the audio sources.

The data that makes me believe it is not the amp:

• when i adjust the volume, the screen shows the volume to be increasing/decreasing, even though there is no actual sound. From what I've read from other GS owners that had bad amps, adjusting the volume did not do anything on the screen (as if it didn't register you pushing the button/adjust volume ****).
• When I unplugged the amp from the connectors, then tried to adjust the volume, nothing showed up on the screen to indicate it registered me adjusting the volume.
• Many ppl who have amp issues report hearing cracking, popping, and/or chirping coming from the speakers. I don't hear anything at all when there is no audio from the speakers. It is dead silent.

The data that makes me believe that it is the amp:

• when I removed the amp from it's "cubby" in the trunk, I noticed that there was handprints all over it, which suggests that someone had been trying to mess with it previously. I just bought this car, and that has me thinking the previous owner tried to troubleshoot the situation, and just traded it in when he realized the cost to replace the amp.
• I've read countless numbers of ppl having amp problems (both ML and non-ML amps). With the sheer number of ppl having issues with these amps, it seems reasonable to suspect that I'm having the same problem.
• Most ppl that have had issues with the amps report issues due to excessive heat (not due to moisture/water intrusion), and I live in TX (lots and lots of heat here).

I'll definitely be taking your advice and tracing the wire underneath the center console. There's definitely something up with that. Thx for the advice.

I'm also going to see if the Sterling McCall Toyota dealership will do anything about this considering this issue came about only 3 days after they sold the car to me. Fingers crossed.

jgscott

iTrader: (1)

There are a bunch of thread about no sound, the volume showing up and many other things you posted. 99.99% is The Amp. Did you check the trunk to see if any water got in or near the Amp back there yet? That normally is the #1 problem that makes it fail. Not heat but water. There is a prone to fail seal place in the truck near the amp.

gemineye

jgscott: I read posts for over 3 hours and didn't find anything about the volume showing up on the screen with no audio/sound, and the fix being a replacement/repaired amp. I'm starting to think you're right though. I did check the trunk for water and it is bone dry. The amp itself shows no signs of being in contact with water, there's no corrosion anywhere (connectors included), and even the compartment that the amp is located in is 100% bone dry (not even the slightest trace of moisture could be felt with my hands) and the car was recently sitting in the rain. I did see that seal (which looks like a 1-way black plastic air vent), and as far as I can tell, it moved through it's full range of motion and seems to be working fine.

Are there any tests that can be run on the amp to confirm that's the problem, or is the consensus that you just repair/replace it and hope that fixes it? It seems like there should be some type of test (ohm'ing out pins?) that would confirm a failed amp. If the amp repair was <$300, I would just give that a shot and hope for the best. But the amp repair will cost more like $800. If that doesn't end up fixing the prob, that's going to sting. Thanks.

jgscott

iTrader: (1)

I've seen the volume show many times, and was the 1st thing that stood out to me you posted. With that connector in, there God knows what going on and what was up? I have suggested here a few times and so have other. Look on ebay, buy a exact compatible known working amp. Make sure it has a return policy. Plug the new amp in and see what you get. I would 1st cut any connection of that added USB and connectors.

Also you can look at a board visually for a problem , but... until you get a schematic, and meter and start checking voltage, resistance, and signals, you don't know if a cap or resistor is bad or not? Seen 100's that looked good till you spec'd it with a meter.

BTW: How many miles on your GS? Did you get it from a Dealer, use/new car? Can you go back and buy a Extended Service Contract? My 13 is still covered and things like this are why I payed a little for a Ext Serv long term coverage.

EAST

Yea I'd be inclined to say a bad amp, just based on the fact that appears to be the root cause in all the people who report back. There was even that one post where the person bought a repaired amp, and that one was bad as well. Their issue was fixed when they bought another amp.

This is probably an act of futility, but out of curiosity, did you unbolt the board to check the underside of it to check for corrosion? Also, did you happen to lift this black covering to see if any of the electrolytic caps had popped or leaked? I would think these caps would be the most susceptible to heat damage of the passive components on the board.



As a side note, if it does end up being the amp, you could probably sell it on eBay for some change.

gemineye

@jgscott i spent some time this weekend to tear apart the entire center console, head unit, and 12.3" display. It turns out that USB port and AUX wire that was plugged into the AUX port were part of some type of external (non-OEM) adaptor to add Apple Carplay to the GS. I removed that entire system and put everything back to stock...and the no audio issue is exactly the same (intermittently works). At this point, I'm more and more convinced that your hunch is correct, and I have a bad amp.

The car is a 2015 GS350 F-sport. I purchased the vehicle from Sterling McCall Toyota dealer in Houston. I tried to get them to fix the issue, but they essentially said the vehicle was not Lexus-certified pre-owned and was an "as is" sale. They offered for me to check their lot and see if I like another vehicle, and if so, I could buy the alternate vehicle and they would apply all funds used towards the GS to the new vehicle. That does me no goo, cause the GS I purchased (white with F-sport package and all the bells and whistles) is not very popular, and they certainly don't have any others on their lot. Thx for the advice on disconnecting that USB/Aux connections. Once I get this issue resolved, I'll reconnect that system for the Apple Carplay functionality.

gemineye

@EAST I read that exact post where the guy replaced the amp, and it was still bad....and he didn't figure it out until he replaced the amp AGAIN with an actual good unit. I feel bad for that guy....that had to be such a frustrating experience.

To answer your question, I didn't unbolt the board and check the underside for corrosion. I did a basic visual inspection looking for black scorching or anything that appeared abnormal. My electrical experience is very limited, and I didn't even think to lift that black covering to inspect the capacitors.....I didn't even know those were capacitors underneath that black covering. Thx for sharing your ideas

jgscott

iTrader: (1)

Sorry the result you had speaking with your selling Dealer. I mentioned this before. Is there a possibly of them getting you aftermarket Extended Service contract being it was just purchased. Finance Managers could get creative and do if they wanted. Like refinancing it with the service contract in. Or if you went through you own bank. Reason I have said this is for years in every forum I always mention the Extender service contract is a good idea. You never know what might go wrong when?

There are other issues a used GS could have like Struts, Engine Vac pump, A/C Servo's motors, Infotainment amp, and a few more.

GrandSedanFan

iTrader: (1)

There also appears to be an aftermarket USB port installed. The prior owner may have installed an aftermarket Carplay/Android Auto module.