Thanks for your reply Harold57, and no offence taken. I have turned the volume **** and the controls on the steering wheel until the HU reaches the max, which is "50" I believe. No sound. I have then gone ahead and set the preset with the steering wheel controls to 25, just in case it magically starts working and it then blows out the fragile old speakers and then I have a new problem. However, I will try what you suggested, thank you.

I also disconnected the battery yesterday for 45 minutes, which should be enough time to allow any capacitor's to drain, and reconnected the battery. Unfortunately, no change.

I think I will dive into the trunk to check all the connections and see if the amp is getting warm and also check the connections on the back of the HU. But the scans I did of the system show that everything is working and communicating! Other than the stereo issue I'm loving the car!

 

Your insight seems correct - thank you. BTW, I like disagreement - mostly because I make a ton of mistakes and can use the corrections.

The 2002 diagram does show a Nav Amp - but that amp receives data from the audio amplifier. Like I said, I have real trouble with diagrams. Even with my reply here (If somehow I was correct) the amp output to the speaker section could be dead and other parts still fully functional.




But like I said, I have a really hard time with wiring diagrams, so i will defer to your opinion.

 

Well, after many more hours of troubleshooting, I think I have found my problem.
It appears that I have two sets of door speakers that are bad. I would have never in a million years thought that could even remotely be possible. What are the odds? But other than plugging in a new midrange tweeter, I have gone as far as I can.
My wiring is good. My signals from my amp and Nav unit are all present and verifiable.
Now I can put my interior back together. I'll put a quick post together on how I did my checks.

Paul

UPDATE: Yes, I did indeed have four blown speakers. I didn't even know you could blow a tweeter out. But the tweeter dome was pressed up against the grill and the midrange was inop. Went to Ebay and purchased one side only for $52.19. I still need the other side now. Just have to wait for a deal.

 

@OntarioSC You might want to do what Raven did and check to see if you are getting voltage to any of your speakers.

But since none of them are working, I would check the AMP first

 

Ontario,
Here’s something you might want to look in. I was playing with the steering column buttons and I found out when you push the voice button it muted the the ML. May be your button was stuck or bad? Worth to check.

 

I can pull the voice button and the little microphone symbol comes up in the top left hand corner of the nav screen awaiting a command. I can tell it to "Turn on Audio," and it turns on my head unit, puts up the antennae and turns on, I'm assuming, the main amp. And when I tell it to "Turn off audio," it turns everything off. So the voice command system is working and her voice comes out of the left side door speakers as it should, which means the nav amp is working and at least those speakers are working.
Does the nav amp not get power from the main ML amp?

 

I don’t have a wiring diagram so I can’t confirm that. Obviously, the Nav ECU is independent with the main amp.
Two things that you can do now;

- Remove the radio, apply external power and speaker to it. Or you can feed it to the home stereo system to verify it's indeed still working.

- If the ML is Ok then the only thing left is the amp. Check all connections, making sure all the plugs are in and tight. I don’t know that there is a fuse to the amp. Someone with schematic can verify this.

Replacing the amp is your last action. Good luck.

 

Ontario.

I wonder have you solved the problem? If you have, what was the culprit?

 

Sorry GmanSC, life got in the way for a few days. I did, however, find time to change the engine oil and filter and also the rear differential oil. Two things that were on my list as well.
Oddly enough, I dropped by a friends place this morning and when I got into the car to leave and started her up... music began to play! I hade left a CD in the head unit and it just started up on it's own. The door was down over the head unit and the head unit was switched off, but as the music started, the door opened up. At first I was confused and thought it was coming out of the left hand speaker where the Nav sound comes from, but then I realized it was full stereo sound! It played for about 15 seconds, cut out for a few seconds, started again for a few more seconds, then quit for good - and the head unit was still powered up and playing the CD.
So, what does this tell me? Bad connection somewhere? Amp is bad and gave one last hurrah? I'm leaning toward the amp, but need some time to dive into the trunk and also check out the connections at the head unit.
The music was short, but of so sweet!

 

I think this is the key to your problem.

You need to see what else is on the circuit that runs the door. It may show in the fuse section of your owner's manual. Maybe you have a loose ground somewhere. If I were to take a "wild, no basis for this" guess, you probably have a loose wire under your center console.

 

Hi guys, sorry It's been a while since I posted about this. Both the wife I ended up with Covid19 for the last week. We've had all our shots so it was more like a bad cold and today we finally tested negative again.

Anyway, I tore apart the trunk today and removed the amp from it's home. I checked for power to the amp with my meter and I have a steady 12.4 VDC. I plugged everything in again and turned on the key. Again there was no sound (I had a CD playing), but when I wiggled the connectors it started playing again. This made me think that perhaps the connectors were just a bit loose, so I put some small strips of Gorilla tape on the ends and bottoms of the connectors to hopefully remove any play in the connector socket. Again, no sound and now there was no room to wiggle the connectors so I wasn't able to produce any sound at all.

Now I decided to take the amp cover off and see if I had anything obvious happening on the circuit board. I looked at everything with a magnifying glass and couldn't see anything that looked over-heated or burned out. So I decide to plug the amp in with the cover off and see if I could get it to play music again. At first nothing, but when I played with the connector for all the speaker connections the sound would come and go as I pushed slightly up and down on the connector. I then stripped back the wire protector a few inches and pulled ever so slightly on each individual speaker wire with some needle nose pliers to see if maybe there was a bad pin connector or loose wire. Nothing.

This leads me to believe there is something going on with the circuit board at this connector. Maybe a cold solder joint that somehow works again if it gets moved to the right spot. I did have the amp playing for about 3-4 minutes at one point before I played with it again and it sounded awesome.
What do you guys think? Should I just send it to United Radio in Syracuse and be done with it? Let me know your thoughts. Thanks.

 

Contacted United Radio in Syracuse and right now there would be a 6-8 week wait time to get the amp repaired once they receive it. The lady said they used to have 8 guys fixing that stuff, but now they train staff and then they leave. The world has certainly changed lately.
So, I decide to order the same 86280-0W070 amp from e-bay that has been tested to work properly and comes with a 90 day warrantee. A little cheaper than United Radio as I only have to pay shipping one way and it will arrive next week.
Taking a bit of a chance, but crossing my fingers that the amp will work fine and we can cruise with tunes soon!

 

Sorry to thread jack, but how is this done?

Thanks

 

No worries doobs, just turn the volume **** on the head unit, or alternatively, you can use the volume buttons on the lower left of the steering wheel to set the volume to where you most often like to listen to the stereo. Let's say that's "25". Now, pull the "SET" button, located beside the volume buttons on the steering wheel, towards you, and this will now set the volume to 25.
Now, when the stereo is muted, either by you or perhaps a phone call, you just press "set" and it returns to 25, which is the number you set because that is where you like the volume. to be at most of the time. Of course, you can adjust the volume up and down manually using the **** or steering wheel controls at any time.

The amp I bought is supposed to arrive on Monday July 25th so I will report back on how that works out.

 

Awesome. Good luck with your amp.