Yesterday I had to make a 5-hour drive to a conference in Lake Placid, and decided to take the big cat since there were four of us. On the way to pick up my companions, I was listening to Acqualung. I turned off the car (music still playing) to load them and their luggage into the car, and then we hit the road.

About half an hour later, someone says put on some music, which I proceeded to do, but no sound was coming out - total silence. Radio, CD, and CDC all seemed to work - you could select them all, see what was playing, but no sound at all.

I Played with the touch screen functions to no avail, and played with the buttons on the steering wheel. The button on the top left of the wheel (icon shows telephone, head and sound waves) produced a "Mute On" message on the touchscreen, so I assumed I had inadvertantly muted the system (no sound from Nav either). I couldn't find the "Mute off" button. The manual seemed to indicate something about a second press of that button, but every press produced the same Mute On message, holding button down same thing. I stopped the car and shut it down, still no sound. we stopped for lunch for over an hour, still no sound.

My companions proceeded to make broken radio jokes for the entire 5 hour ride, and each of them took a crack at trying every button in the screen and on the car, searching the interwebs on their smartphones, etc. - all to no avail.

Many hours later - toward the end of the night - and with many stops in between, we all pile in the car after dinner, start it up, and it was mysteriously working again.

I searched the forum and see that others have had the mysterious mute issue, but i don't see any resolutions for it... Is there really no fix for this? I was sure I would find the simple answer I was overlooking here, but apparently not?

I don't have an ACM or USB port, it's a 204 XJR with one CD in the dash and a 6-CD changer in the trunk. I saw reference to shutting down while stereo is playing causing this, and I did do that yesterday (but won't do again). I also saw suggestion that changer unit may cause this issue (I'll avoid using that too.)

I also saw mention of periodic 1 to 5 second "pauses" in the audio system - and I do experience those fairly regularly. I had assumed those were CD-related since i never listen to the radio.

At least we will have music for the ride home Thursday, but that was pretty frustrating.

Is there an un-mute button somewhere that I missed?

Any advice or thoughts on this??


2011 thread (unresolved) on this topic:
https://www.jaguarforums.com/forum/x...o-sound-62711/

 

Sounds like you did everything except turn the ignition off and on again!

This is a common fault on this Jag, if you are lucky (like me) it will

not happen again for 3 years!

Source of fault is unknown AFAIK.


You could tell your friends that the ECU can't think with the music on,

they might believe you ...........briefly.

 

Thanks - but I did turn the ignition off for extended periods before it came back on.

I guess I'll just have to hope it doesn't happen again.

 

One question. Has the nav system ever been updated? The nav update DVD that came out a few years ago included a software update for the touchscreen system. It's a shot in the dark, but you never know...

 

Same thing has happened to my XJR a couple of times, the X-Type I had also did it a couple of times too (same audio system).

I think that for whatever reason the amp doesn't "wake up" properly when you start the car. It always resolved itself by restarting the car.

Just one of those things...

 

So the mystery mute issue resolved itself for a while. But now it's back, and I'm starting to form a hypothesis...

Its hotted up in NY lately, lots of 90+ degree days. When i take the car out of the garage to go to work in the morning, audio is A-Ok. When i come out of the office 8 hours later and get in the car to go home, it's mute. the next morning, its fine again. I'm starting to think it has something to do with the fact that it's sitting in the sun for hours and getting hot. And it is a black cat, so maybe it's even a little more hotter than average.

Anyway, when it's gone mute, you can no longer select the CDC (CD Changer) from the touchscreen, or the CDC button below it. You can still select Radio or Dash CD - neither of which produces sound at all. Until the next morning after it's sat in a cool garage. One time after going Mute it was in the garage for about 2 hours and came back to life.

Does that heat theory make any sense? I read somewhere here that the components have to boot up in the proper sequence on their fiber optic network or the thing goes all mute, and I'm thinking the CDC in the trunk is overly hot and not booting (hence the inability to select that device.)

Another Q... before I go to the dealer for a many-hundred-dollar new Jaguar-branded CDC, can i just get one online and install it myself? or am I going to run afoul of the radio code gods by trying to do that? (the radio codes were thoughtfully left in the compartment by the previous owner, so i have those.)

Even better - can I put a hard drive/SSD in instead of a CDC? Or can I eliminate the CDC entirely by removing it and just live with the dash CD?

 

I certainly sounds as if you have identified a reason for your on/off faults and when you think about it there is no insulation behind the electronics in the boot also a black car will absorb more heat than other colours.

Personally I would remove boot lining and wiggle/check connections at rear of cdc and at the same time insert some insulation behind the audio/nav stack if there is room.

Maybe also leave the lining off for the time being.

Don't even consider a dealer-there are auto hi fi guys who could sort it I am sure.

 

So two years later - after tolerating intermittent outages on hot days - and having it work just fine on other hot days - the problem got worse - the audio quit entierly a few weeks ago and isn't coming back. So I finally made an appointment and took it to the dealer today.

Taking it to the dealer was an unpleasant experience. They moved to new quarters 2 weeks ago, and they now only have one working bay, two mechanics, and one service adviser who seems like he hates his job. I asked about the "shrinkage" and got a "not so many being sold anymore" response, followed by "new models may help reverse that trend."

SO i left the car and they checked the wiring loom connections in the trunk, all of which seemed to be in order. They called and left me a message saying "this car has problems." I went back over there in person to ask whaddayamean problems?

The "problem" is that they need to take the console apart in the front to check the wiring loom connections at the back of the head unit, and they didn't have time to finish it today - so they decided to leave an ominous-sounding message instead. Nice.

I told them to keep the car since I can drive the X in the meantime. He said it might take "many hours" to check the front connections. I reminded him that service manuals provide time estimates - and those aren't expressed as "many hours." The service tech then revised it to 3 to 4 hours - at $150/hr. I approved 3 hours. Their suspicion is that the connection was wiggling loose - which would account for the previous intermittent behavior - and has now become disconnected.

Unfortunately the old service adviser - who was great - retired last year. This guy refused to reveal any service history for the car (which I bought used 3 years ago) even though it was right there on his screen. I don't think they actually want any customers at this place. I'm rapidly losing confidence in them, which is a shame.

Any thoughts out there on the wiggly-connector theory?

 

"Don't even consider a dealer-there are auto hi fi guys who could sort it I am sure."

I have an idea it may be the D2B link ie a connection on the optical link but

I can't remember why I think that is the case. lol

 

Meatbag, had similar issues with mine for short periods which gradually got worse, see my thread here about it https://www.jaguarforums.com/forum/x...tently-154827/


Evan Trinh gave some good advice about the fibre optic cable, which I've replaced and no issues to date and that was some time ago.
The fibre optic cable wasn't too expensive either so may be worth looking into and or trying.


Jim

 

Thanks Jim. I saw that thread, and read it carefully way back when - and again before I raised the topic today. I have occasionally encountered the brief moments of silence problem you describe too.

When I first read up on this 2 years ago I found myself wondering why on earth you would need (or want) fiber-optic cable in a car audio system - and i'm still wondering about that. Where do these fiber cables start and end? and why use them instead of copper?

 

Optical cables are not prone to EMF interference from the spark plugs and other electricsl stuff in the engine bay.

They start at the head unit (the single CD + radio in the console) run along the car to the trunk, then come back in a giant ring. If the ring is broken anywhere - by faulty cable or faulty device the whole system stops working.

If the problem is persistent a dealer tech who is worth his salt should be able to find the cause in a few hours.

There is a fiber optic diagnostics in the nav hidden menu as well.

 

So the car was at the dealership for five weeks (yup, five) and I finally went and took it back from them in the same condition it was when I dropped it off - no sound. They didn't charge me anything for it, though I think they did leave a few new scratches in the paint that I didn't notice until I washed and waxed it this past weekend.

Very disappointed in the dealer. I've had good experience with them in the past, but I don't think I'll be going back there for anything any time soon. I had to call them once a week to find out what was going on, and the answer was always the same - "its an old car, we're working on it as time allows, it might cost more than the car is worth, we will let you know."

After the first week they said they had tested the amplifier and the CDC, and both were good. I am skeptical they really tried to fix it at all past that point given the service advisor's attitude - I think they may have just parked it on the side until I was tired of waiting and came to pick it up.

Anyhow, I'll be taking it to a car audio place next, and telling them that the problem is most likely the fiber optic cables. I just re-read Jimc64's audio thread again, and it does seem that in the end it was fiber cables that were the problem there, and I suspect the same may be true here. What a PITA.

 

I can confirm that if the fiber optic loop is broken (ie, disconnected, loose connection etc) this exact symptom will happen (no audio from any source). When I installed the VBox the fiber optic connection was loose and lost all audio when it wiggled itself out of the socket. Once I re-installed it the problem was alleviated.

So I do believe the loose fiber optic connector theory or possibly (which would be bad) an internal breakage of the fiber optic cable.