What AlexD did was impressive. I'm not so sure I would want to go through the process of rebuilding a double din like that. Here is an alternative that I think would be a fantastic option. A bit more expensive but it gives you so many features. The Kenwood KOS500 is a Factory system expansion control. The KOS500 gives you all the funtionality of an aftermarket receiver.

compatible with optional Kenwood iPod adapter, satellite radio tuner, Bluetooth adapter, navigation system, TV tuner, backup camera input
inputs: USB input, two sets of A/V inputs
outputs: three sets of preamp outputs, one set of A/V outputs

The unit has its own amplifier so you can remove the stock headunit and connect the KOS500 directly into your speakers. I don't know if it would work with your current display so you will likely have to purchase an aftermarket display but installing it to your bezel will be much much easier than chopping on a legitimate double-din. Here is the link:
http://www.crutchfield.com/p_113KOSV...-KOS-V500.html

 

From Crutchfield.com:

Features

Overview: Kenwood's KOS-V500 Advanced Integration A/V Controller lets you build an A/V system in your vehicle without replacing your factory radio. You will be able to enjoy navigation, satellite radio, Bluetooth technology, and HD Radio through your factory audio system when using this device. You also get high-speed iPod control of both audio and video. In addition, the KOS-V500 is capable of outputting a 4-line text display for Satellite Radio, iPod, HD-Radio and RDS information.
Radio Compatibility: The KOS-V500 can be installed to any factory or aftermarket deck by hardwiring the supplied harness to your existing audio system. The KOS-V500 features a sophisticated menu system and comes with an IR remote for complete control. To view this on-screen display and menu system you will need the optional touch-screen Kenwood monitor (KOS-L702/KOS-L432, sold separately) or a special Kenwood adapter (sold separately) that converts the 20-pin proprietary monitor output to a standard composite video output so you can hookup your factory monitor or navigation screen.
Remote Control: This unit is equipped with an IR remote control and an IR emitter attached to a cable that plugs into the KOS-V500 and then is run to the front of the vehicle so you can use the supplied wireless remote control. The remote can operate the power, source, playback and menu functions of the KOS-V500.
Built-In Amplifier: The Kenwood KOS-V500 features an integrated Mosfet 22 watt RMS x 4 channel amplifier that you can choose to use instead of your factory radio's amplifier to upgrade your factory audio sound. A speaker-level adapter harness is provided to supply connection for the audio signal from your factory radio to the KOS-V500. The built-in amplifier utilizes a separate gain control to match your factory radio's speaker-level output.
Preamp Outputs: The KOS-V500 also features three sets of 2-volt preamp outputs (Front, Rear, Subwoofer) for connecting external amplifiers to your factory system for added audio performance. The speaker-level adapter harness will also be used in this type of application as well.
Built-In Tuner With RDS: The KOS-V500 has a built-in Kenwood CR-2 tuner which provides high signal strength for clear radio reception. The tuner features the Clean Reception System Circuit (CRSC) for improved rejection of distortion due to multi-path. You can choose one of three tuning modes: Auto 1 (seek tuning), Auto 2 (cycles through and tunes the selected band's preset stations only with each button press), or Manual. The unit's tuner features RDS (Radio Data System). RDS is a service used by some radio stations to transmit data outside of normal radio broadcast signals. When an RDS station is received, you can immediately find out what kind of data is being transmitted by looking at the program service name which appears in the display after the frequency on the optional Kenwood monitor or your factory screen. RDS features an emergency transmission function which interrupts regular programming to broadcast an emergency announcement (such as a tornado or severe storm). There is also a switchable Traffic Information function, which will automatically tune a traffic bulletin when it is broadcast, even when you're not listening to the radio. The unit utilizes a female Motorola plug attached by a 6" pigtail to the chassis and 19.5' foot antenna extension cable is provided for installation.
Source Compatibility: You can listen to various sources through your factory car stereo by using the KOS-V500. Below is a list of available sources that can be connected.

• Portable or 12-Volt Audio/Video: The unit features a set of audio/video 3.5mm inputs on the front panel of the unit. There is one stereo 3.5mm input for audio and another 3.5mm input for video. The A/V AUX input can be used to transfer audio and video signal from your portable MP3/Photo/Video player. The unit also features 2 sets of RCA A/V inputs that can be used to hook up an external DVD, VCR or Video Game system.
• AAC-LC/MP3/WMA/JPEG: The Kenwood KOS-V500 features a front panel 2.0 USB type-A port and 11.5' USB cable that supports the transfer of AAC-LC, MP3, WMA and JPEG files. The USB port enables connection to portable USB mass-storage players, USB thumb drives and audio control of MP3 players. The USB port is compatible with all USB mass storage class devices that support the FAT16 or FAT32 file system. A single or multi-slot card reader can also be connected the USB port, allowing your music or photos to be put neatly into different types of memory cards. Your USB device's rechargeable battery will recharge while it's connected to the USB port and when the KOS-V500 is turned on.
  Note: The iPod nano and iPod video can be hooked up directly via USB, but without the Kenwood adapter cable (KCA-iP300V), you will not be able to play iTunes or other copyright protected content and you will lose any audio/video file browsing control.
  
• iPod Control: The USB port and A/V AUX input are also compatible with iPod devices when used with the optional KCA-iP300V adapter (part number 113IP300V, sold separately). The USB Direct Connection enables high-speed iPod data communications of 12MB/bps via the optional KCA-iP300V (3-Wire) interface. One end of the cable plugs directly into your iPod's dock connector while the other end of the cable uses three connectors that plug into the front of the KOS-V500. The USB type-A connector portion of the cable plugs into the unit's USB port and handles the control and charging of your iPod, so you can navigate through your music and video files using the supplied remote control or optional touch-screen monitor and view song and movie info on the optional display. The two 3.5mm miniplug connectors of the cable plug into the unit's A/V 3.5mm inputs and transfer the music and video from your iPod to your factory audio system and optional monitor. By using the Auxiliary input, the music travels to the receiver as an analog signal, so you can even play the Digital-Rights-Protected files you've stored on your iPod. The controls of the unit's on-screen display when used with Kenwood's optional touch-screen monitor (KOS-L702/432, sold separately) are seamless when used with the optional KCA-iP300V and include metadata browsing and playback of DRM contents, as well as the ability to choose any iPod playback mode to suit your listening application. The following iPods are compatible with this unit - iPod video (5th generation), iPod nano (3rd/4th generation), and iPod classic (80/120/160GB).

• Satellite Radio Ready: There are several options for connecting an optional XM or SIRIUS Satellite Radio receiver to this receiver:
  • XM Satellite Radio: To receive XM Satellite Radio, you can connect the optional CNP2000UC XM Mini Tuner and the CNP-KEN1 Kenwood adapter cable (package item number 700XMKEN1).
  • SIRIUS: To receive SIRIUS Satellite Radio, you can connect the optional SC-C1 SiriusConnect vehicle tuner (item number 607SCC1) and the Kenwood/SIRIUS adapter (item number 113KCASR50).
  • Dock: Select dock-and-play and portable SIRIUS radios can be controlled using the Kenwood/SIRIUS adapter (item number 113KCASR50) and the SC-VDOC1 dock (item number 607SCVDOC1).
  • Auxiliary Input: A portable satellite radio receiver, such as the Delphi SkyFi3 or SIRIUS Sportster, can be connected to the head unit via the auxiliary input (adapter may be required).
    • Note: A subscription is also required to receive satellite radio programming from SIRIUS or XM.
• HD Radio Ready: With an optional Kenwood HD Radio tuner (item number 113HR100TR), you will be able to receive digital AM/FM broadcasts from local stations where available. This new technology will significantly improve audio quality and reception, as well as include information such as artist name and song titles or traffic news, viewable on the optional Kenwood monitor (KOS-L702/432) or your factory monitor using a Kenwood adapter.
• TV Tuner Compatible: This unit is compatible with the Kenwood KTC-V300N TV tuner (sold separately, item number 113KTCV300).
• Navigation Ready: The unit is compatible with the following Kenwood navigation systems: KNA-G510 (item 113KNAG510), KNA-DV4100 (item 113KNADV41), KNA-DV3100, and KNA-DV2100. The navigation system can be connected via the 13-pin I/F jack on the front of the integrated A/V controller (I/F cable supplied with the navigation system). Third party navigation systems with composite video and stereo RCA outputs can also be connected via the AV input. You can select which speakers are used for navigation voice guidance: front left, front right, or both front speakers through the unit's menu. You can also set the volume for the voice guidance audio.
• CD-Changer Compatible: This unit is compatible with Kenwood changers manufactured in 1998 or later. If the changer has an O-N switch, the switch will need to be set to the "N" position.

Audio/Video Output: The unit has a single audio/video output consisting of a pair of composite RCA terminals for audio and one composite RCA terminal for video to hook-up an external monitor such as a head-rest monitor. The A/V output is used only to output a connected video source and does output the unit's menu system.
Bluetooth Ready: The unit is also Bluetooth compatible using the optional Kenwood KCA-BT100 Bluetooth adapter. Using this adapter you can make and answer phone calls from the optional touch-screen monitor (KOS-L702/432) or supplied IR remote. You can even download your Phonebook information from your compatible mobile phone into the KOS-V500. You are able to register up to five compatible Bluetooth cell phones when using the KCA-BT100 adapter.
Steering Wheel Remote Compatibility: The KOS-V500 has a steering remote control lead attached to the main-harness. When used with the optional SWI-JACK interface (item number 127SWIJACK), you can retain the use of your steering wheel and/or rear seat radio controls when connecting additional audio/video equipment to your factory radio via the KOS-V500. The SWI-JACK is compatible with over 95% of the vehicles made from 1986 to the present. Compatible vehicles include many Acura, Audi, BMW, Buick, Cadillac, Chevrolet, Chrysler, Dodge, Ford, GMC, Honda, Hummer, Infiniti, Isuzu, Jaguar, Jeep, Kia, Land Rover, Lexus, Lincoln, Mazda, Mercury, Mini, Mitsubishi, Nissan, Oldsmobile, Plymouth, Pontiac, Saab, Saturn, Suzuki, Toyota, and Volkswagen vehicles and Harley Davidson motorcycles. Please consult the Crutchfield Vehicle Selector to see if your vehicle is compatible.
Stand Alone Compatible: In addition to connecting this unit to your factory system, the KOS-V500 can act as a stand alone unit due to its built-in tuner and amplifier along with its various source inputs when used with Kenwood's optional KOS-L702 or KOS-L432 touchscreen monitor.
Security Code: You may program the unit with a 4 digit security code. Once the unit has been programmed with a security code, the code must be entered to use the unit after it has been disconnected from power.
On-Screen Menu: The Kenwood KOS-V500 features an on-screen menu that is output from its 20-pin monitor-out connector. You will need the optional Kenwood touch-screen monitor (KOS-L702/432) or an optional Kenwood interface that adapts the proprietary 20-pin monitor output connector to a standard composite video output so you can connect the KOS-V500 to your factory monitor or navigation screen. The on-screen menu can be controlled through the touch-panel of the optional Kenwood monitor (KOS-L702/432) or through the remote when connected to a factory or non-touch-screen display. You can view and control the following audio and video settings through the unit's on-screen menu.

• Audio Settings:
  • System Q EX Sound Control: Six EQ curves are preset into memory, allowing you to recall the best preset EQ curve for different types of music. The preset curves are named "Natural", "Rock", "Pops", "Easy", "Top 40", and "Jazz". In addition, you may store your own settings under the "User Memory" EQ curve. In the User Mode you can make manual adjustments for the bass center frequency (40, 50, 60, 70, 80, 100, 120, or 150Hz), bass level (-8 to +8), bass Q factor (1.00, 1.25, 1.50 or 2.00), bass extension (On or Off), middle center frequency (500Hz, 1.0kHz, 1.5 or 2.0kHz), middle level (-8 to +8), middle Q factor (1.0 or 2.0), treble center frequency (10.0, 12.5, 15.0 or 17.5kHz), and treble level (-8 to +8). The System Q EX can be turned off in the menu, still allowing you to adjust the bass, middle and treble levels only.
  • Speaker Type Setting: This feature tailors the System Q EX Sound Control settings according to the type of front speakers in your vehicle. You may select Standard (for speakers with a general diameter), Narrow (for speakers with a small diameter), Middle (for speakers with a medium diameter), or Wide (for speakers with a large diameter).
  • System E's+ Advanced Crossover System: The System E's+ Advanced Crossover system allows you to tailor your system with selectable crossover points for all channels. For the front and rear channels, there is a high-pass filter with independently selectable crossover points of 40Hz, 60Hz, 80Hz, 100Hz, 120Hz, 150Hz, 180Hz, 220Hz or Thru (no filter). The non-fading preamp output, for use with subwoofer amplifiers, has a low-pass filter with a selectable cutoff frequency of 50Hz, 60Hz, 80Hz, 100Hz, 120Hz or Thru (no filter). You can also switch the phase of the subwoofer output from normal to reverse, and adjust the level of the output from -50 to +10 in 1dB steps.
  • Bass DC Extension: When this feature is turned on it extends the bass center frequency to the low register by approximately 20% adding additional bass response to your system.
  • Bass Management System (B.M.S.): This unit is equipped with an interface (pink/black wire in the wiring harness) which controls certain special features of B.M.S.-equipped Kenwood eXcelon amplifiers. This unit, when properly connected, can remotely activate and adjust the amount of bass boost in the amplifier. You can choose between +6dB, +12dB, or +18dB bass boost, or flat (no boost). In addition, you can lower the bass boost center frequency by 20%, switching between "Normal" and "Low".
• Video Settings:
  • Selectable Screen Modes: You can choose from the following Screen Modes for the display monitor for each of the video inputs (iPod Video, Video 1 and Video 2).
    • Normal: displays 16:9 widescreen format pictures that fill the entire screen width, and 4:3 (conventional TV) pictures display with black bars on either side
    • Full: expands 4:3 pictures horizontally to fill the entire width of the screen, distorting the picture slightly but retaining full image height
    • Just: expands 4:3 pictures horizontally only at the edges
    • Zoom: expands 4:3 pictures both horizontally and vertically, filling the screen without distorting the picture but cutting off the top and bottom edges
  • Display Adjustment: You can adjust the display's brightness, contrast, and black level.
  • Backgrounds: The unit features backgrounds that can be selected from readily available patterns or you can create your own by using original pictures or images downloaded from your portable USB device.

Inputs and Outputs

Rear Panel:

• Antenna In: female Motorola antenna input for connection for connection of your factory antenna when using the KOS-V500's built-in tuner
• Power: 22-pin power connector input to supply power to the unit and send signal to your factory audio system
• Monitor I/F: 20-pin jack that connects to an optional Kenwood monitor (KOS-L702/432, sold separately) or a Kenwood 20-pin to composite RCA adapter
• Monitor Power: 2-pin plug that connects the supplied power/ground harness which provides power to the connected, optional Kenwood monitor (KOS-L702/432)
• R-Cam: RCA composite video jack for use with an optional rear-view camera (CCD-2000)
• A/V Output: left and right RCA audio jacks and an RCA composite video jack to supply video to an optional universal monitor
• A/V Input 1&2: two sets of left and right RCA audio jacks and an RCA composite video jack for inputting an audi0/video signal from an external source
• Pre-Out: left and right RCA audio jacks for the front, rear and sub-channels that connect to optional amplifiers in your system

Front Panel:

• Relay Unit: 4-pin input for supplied relay harness
• Remote: 3.5mm input for supplied wired emitter to control the supplied IR remote and a 3.5mm output to link another you to IR remote controller
• TV-Tuner I/F:20-pin proprietary jack that allows you to connect an optional Kenwood TV tuner
• USB: USB connection for audio digital devices
• iPod: 3.5mm stereo audio and video jack for connection of iPod or other portable audio device
• Speaker-Level Input: 10-pin jack for connection of supplied speaker-level adapter to transfer the audio signal from your factory head-unit to the KOS-V500 when using the unit's internal amplifier or external amplifiers
• Navigation I/F: 13-pin jack that allows you to connect an optional Kenwood navigation unit
• 5L I/F: 13-pin jack that allows you to connect an optional Kenwood changer

 

Jon, Although a DPDT switch will work, the fundamental issue is that one source (the AUX) will be in the cabin while the other source (the CD changer) is in the trunk, with the cables that you want to drive with either source already being at the CD changer. SO, if you just use a DPDT switch, you'd have to first route the CD source signals up to the cabin, then select the AUX or CD with your switch, then send that selected signal BACK to the trunk (boot) to insert into the cables that led from the CD to the amp or head unit... so, for the CD, you've now added an additional 10-15 feet minimum of signal path, just a long antenna to pick up niose and alternator whine, etc...

With the relay, the selection is performed right at the CD changer, controlled by a switch in the cabin which either sends 12V to the relay or not, depending upon which source you have selected. Yes, the AUX cable is going from the cabin to trunk, but you have no choice here.

Will a simple switch work? Yes. Does it add some risk to getting quality sound? Yes.


By the way, I have a US XJ8 (2000) and my radio head unit DOES require a code if power has been removed.

 

Hi Again,

You make very good points. Are you sure you're not an electrical engineer AND a defense attorney??? I will re-examine the relay idea and see if I'm on-the-ball enough to implement it in my vehicle too.

As far as the code goes-weird. I had my radio physically out of the vehicle for 3 days and put it back with no code needed. And the replacement unit I had bought also did not require a code.

I have the 2000 XJR with "premium sound". Could that be why?

Thank you,
Jon

 

I have the 2000 XJ8 with Premium Sound, so I expect they're the same systems.

I had been told again and again here in the forum that US radios did not require a code, yet mine did... so all I can tell you is that if you don't, good! I suspect I'm in the minority.

 

the premium system (alpine ) use the same radio than the regular one, the back of the radio has a switch to change between premium and regular.
While it is true that most radio in the US do not require a code, the code function can turned on or off by any dealer,so it's possible to have a radio that need a code in the US.
i have 2 spare radios, 1 that i bought here in the US and another one in the UK, they are both exactly the same and they both require a code ( the code is specific to the radio serial number) but the one in my car ( 01 xjr) do not require a code

 

@ 3down

Interesting post. I'd never seen one of those things before. The only thing I can't quite follow is could you use it at all without the screen ? I'm guessing the remote would have something like "source select" on it, so you could just toggle through until you got the correct music playing ?

Compared to some of the XK8s that have the Nav screen, the XJ8s are a real pain in this regard because there was never a factory option to have a "proper" nav screen.

Just shows there's always more than one way to skin your cat :-)

 

SARC

I think there would have to be a video interface via a link to the current display or to an aftermarket display.

 

If you review my post #3 in this thread, this new message will make more sense...

I had purchased another radio (which also did not work, sadly) but it worked well enough to test the audio on some sources, such as the CD. Interestingly, the sound problem STILL appeared! This means that the problem is very likely NOT in the head unit! I removed the new head unit and replaced my original head unit.

I am now going back to troubleshooting the amp. To recap:
1) Sound from all sources (AM/FM/Tape/CD) is perfect for about 10-20 minutes before degrading into a digitized white-noise. I will post a recording of this if anyone is interested...

2) Sound from ONLY the NAV source remains PERFECT even when this white noise appears. Thus, if the CD audio is corrupted but I keep it playing then the NAV audio voice prompts overlay the CD audio and the NAV voice prompts are in perfectly clear, crisp audio.

Since all audio sources go through the amp and all audio sources except NAV originate in the head unit, I theorized that the head unit was at fault. But this is not the case.

This tells me that the amp has different circuitry to amplify sound from the NAV versus the head unit--something I did not expect.

The fan in the amp is spinning but the problem seems to be heat-related. On warmer days the sound degrades to white noise more quickly than on very cold days.

I am now seeking an amp replacement, so I may start a new thread on just that. I wonder if I can just buy an aftermarket amp for my system but I am guessing that, with the AI-Net and other proprietary connectors, this won't be possible.

Any comments about this?

Regards,
Jon

 

Well, I guess no one had any thoughts on my audio issues beyond what was already said.

I ordered a new amp. I will post the results of its installation once its in the car.

 

Typically - when the output of a device slowly degrades to 'white' noise - or shott noise, it is because a transistor somewhere in the circuit is going into saturation - either from thermal runaway or a leaky base coupling capacitor that heats and the leak gets worse and drags the transistor into saturation, or something of that ilk.

If you've isolated the issue to the amp (by using multiple head units as sources) then a new amp is probably (just probably) a safe bet.

The only issue is that the Nav continues to work... IF (and only if) the Nav audio is fed to the amp separately, then I would suspect the amp's input circuit for the head unit's audio has the bad component.

EDIT: I have looked at the wiring document - and for the 2000 XJ8 Premium Sound, at least, (don't remember what you have) there is a problem... the head unit's audio goes into the Navigation Control Module first, and from there, the audio goes to the Amplifier - combined for Nav and the head unit. This suggests to me that the failed component is in the Navigation Control Module, not the Amplifier.

If your year/model's wiring is the same (refresh my memory and I'll check), I'm 99% certain the fault lies with the Nav module.

If one could get it open, I'd look for bad solder joints. A bad joint has been known to change it's resistance as it heats up, causing the kind of symptoms you're seeing... of course, it could be failure in another component, as described earlier - but a bad solder joint is relatively easy to see and would be a nice, simple, miracle fix.

 

@QuadManiac:

You're turning into my favorite human being.

What you say makes a lot of sense. I am very intrigued by your thoughts regarding the navigation system as the "central conduit" through which all pre-amplified output passes. I never had considered that before. My amp takes two separate white muti-wire connectors, and I assumed one of them was from the head unit only because the back of the head unit has a similar white connector on it. Earlier in this or another thread I had mentioned to those who might not realize it that the navigation audio has a separate volume adjustment from the head unit. This at first suggested to me that it was the head unit that was separating the nav audio from all other audio sources. But because AI-Net is a partially (wholly?) digital interface, I suppose it's possible that the head unit is simply sending digital instructions to the amp (or nav unit?) to adjust the sound of the nav separately from the other audio sources. Once I determined that the head unit is not the failed component, I assumed that the amp must have two separate processing circuitry for nav audio and other audio. Also, the nav system is able to lower the volume of the other audio when it needs to prompt the driver with audio navigation messages.

I never have removed the nav box from the vehicle nor have I ever needed to disconnect it. If it has a white connector going from it to the amp then it seems that in my system the head unit and nav unit each have their own harnesses going into the amp--which suggests the amp is the culprit in my configuration (unless somehow the amp feeds back into the nav unit, which, considering everything else I've learned, is entirely possible).

The new amp is on its way so I will have some answers soon. In the meantime, I have some additional information for you and some questions:

1) The audio now is degraded to "white noise" almost as soon as I get into the car. Temperatures in TX have been near 70-F. When temps were around 40-F, I was able to play the system for about 20 minutes before it degraded. This seems to indicate that temperature is a primary factor, as I have always suspected. (The fan on the amp is indeed spinning.)
2) I have attached a sound file to this message to give you a sample of what the "white noise" sounds like. If you listen carefully, you can hear that it is not pure white noise; rather, it is white noise with digital-sounding artifact…

Questions:

A) If I were to open the nav unit and see a leaked capacitor, would you say it's likely that replacing that capacitor would be enough to fix the system? Or do other parts get damaged when capacitors leak?
B) How do you test a transistor and, if fault, can they just be replaced too? Can they be tested in-place (on-board) or do they need to be desoldered and removed first?

Thank you for all your insights and advice.

Regards,
Jon

 

By 'leaky' capacitor, I am talking from an electrical perspective - it's not leaking fluid externally, it's leaking electrons internally, so there is usually no visible evidence.

Unless you are a competent electronics technician or engineer, with either an innate understanding of the circuitry or with a schematic of the device in hand, you are not likely to be able to troubleshoot any of this from an electronics standpoint.

However, one can visually look for a bad solder joint - and I think this is all that you can hope for. One can look at each pin soldered to the circuit board, on both sides (in through hole solder joints) and look for a separation between the wire/pin and the surrounding solder. A good magnifying glass helps. A bad solder joint is more likely than a failed component... electronics components - resistors, transistors, capacitors, are very reliable... it's the installation labor - the human involved - that is less reliable, most often.

I have heard this sound before, can't remember where, but it was a very long time ago... and it could well be due to a bad solder joint. So, all I can suggest is a good inspection, if you can get into the module; but keep a backup plan for replacement. Start looking now, and you might find a used unit at a reasonable price.

 

Well I can definitely recognize a bad solder joint: I soldered many a Heathkit device together...

I neglected to mention again that this all started with (it's a long story so here's the short version) moisture in the trunk. I had to rinse the carpet after a food-spoilage spill/leak after hurricane Ike. I had rinsed the carpet and placed it back into the trunk while still damp because I was away from my home and had nowhere to hang/dry the carpet. Maybe a month later, this all started. That's why I was always skeptical that it was the head unit. I am quite certain that moisture was the original culprit.

But that moisture incident happened about two years ago so I'm sure any trapped moisture is long gone. But perhaps the moisture caused an already bad solder joint to somehow oxidize, causing this issue...?

I did not get from your last post whether you are convinced that the problem is in the nav unit or whether you still think it may (based on the two connectors I mentioned) be in the amp. I would like to try the new amp before buying a new nav unit. Heh heh--I am going to end up with an entire second audio system in parts I bought but that did not solve the problem! At least I will have backups for almost everything!

Regards,
Jon

 

Hmm, I still think it's in the Nav... but since you have an amp on the way, that's an easy way to know for sure.

The Nav is in the trunk too, isn't it?

THe wiring diagram shows the audio going from the radio/cassette unit to the nav and then from there to the amp. (see attached schematic below). This is 2000 XJ - that's what you have isn't it?

 

Hello,

Sorry, yes--I have the 2000 XJR with the "premium sound" package. The Nav, Amp, and CD Changer are all mounted in the trunk.

I looked at your diagrams and I see how this is a surprising/confusing issue (at least to me). I for one did not expect the Head Unit to first connect to the Nav unit before going to the amp. This would suggest that you must have a working and present Nav unit in order to have a working Head Unit--and that seems wrong. But, then again, it would seem one way to integrate the Head Unit's ability to modify the Nav volume before combined Head Unit/Nav audio is sent to the Amp.

To help reconcile your diagrams with the reality of my 2000 XJR "premium sound" system, I grabbed images off of the web (it was easier than taking images of my equipment, especially units I have not removed from the vehicle). The attached images are therefore not images of my actual equipment but they do match what I have.

I then annotated the images with labels. All labels are 100% accurate--but one is a guess. I can only assume that the AI-Net cable coming from the Head Unit is the one that goes to the Nav unit. I say that based on a process of elimination, but cannot yet verify it because I did not have time to un-mount the Nav unit from its solid, unwieldy, and seemingly disaster-proof mounting brackets.

But adding these labels helped me better understand how and why the Nav unit might in fact be the problem--a real shocker for me and I imagine anyone else reading this thread. But they do align with what your wiring diagrams suggest.

At first blush, I couldn't quite get past the "design flaw" that this represents! It suggests that if the Nav unit fails then the Head Unit is rendered inoperable (in the sense that it will appear to be working from within the vehicle but won't produce any amplified sound!).

But then I thought myself that perhaps the male AI-Net cable that comes from the Head Unit and goes into the Nav unit can instead be plugged into the Amp in lieu of the Nav unit. This would allow Jaguar to sell the Nav unit as an option. This would also bypass Nav and get the Head Unit connected directly to the Amp. It seems that this should work and that since the AI-Net genders coming from the Head Unit and coming from the Nav unit are both male, that either one can be physically plugged into the female AI-Net location on the back of the Amp. Of course, I realize that I will give up the Nav system in doing this, but it might be a way not only for me to determine if the Nav unit is introducing the "white noise", but it might also be an effective "fix" for anyone with this configuration who loses the Nav unit and still wants Head Unit functionality without overhauling the sound system.

I will try to switch those plugs and hope that nothing catches on fire after doing so. If a fire results then I will post the video of it in a new thread called "Do's and Don'ts of Alpine AI-Net".

Thanks again for all the help. I'll let you know what happens next...

Regards,
Jon

 

Try plugging the head unit's cable (that plugs into the nav) directly into the amp as you brillliantly thought. THis may not be possible, due to the sex of the connectors, but I do not have the Nav, and the head unit's cable plugs straight into the amp... so i would expect yours could too. definitely worth a try to see if things now work - we both thought of this separately - great minds think alike!

So, yes, I would expect it to work, so Jag could sell the Nav as an option without having to change the wiring harness in the process.

 

@QuadManiac:

Thanks for the quick reply. Yes indeedie--I think we're on the same page on this one!!!

The genders DO match up and I did successfully plug the Head Unit's male AI-Net end directly into the Amp rather than into the Nav unit. I did so by leaving all other wires intact and only removed the Nav AI-Net from the Amp (letting it dangle free) and replaced it with the Head Unit AI-Net cable as described. (Interestingly, the Nav option on the Head Unit still shows its menus--I imagine all the data/display of Nav will work fine but that I simply won't get voice prompts. That's even better because I have a road trip coming up and can still use Nav and the radio (if this all works) without losing all Nav features. I'll confirm if Nav works fully without audio only when I update this thread later.)

THE HEAD UNIT SOURCES ALL WORK FINE with the new direct-to-amp connection! Now, I have to drive around and see if the sound degrades... I will go to dinner across town tonight so it will provide an excellent opportunity for me to confirm whether this sounds is now okay. If it is then you, sir, were correct all along--that the Nav unit is the problem. If that's the case, I will remove and open that up and inspect the inside for any solder joint issues, etc. And if that's the case it seems ironic to me that the one sound that was working all along (Nav audio) was from a unit that in fact was the culprit all along (the Nav unit). Amazing.

However, if the sound does degrade into "white noise" tonight, then I think it must be the Amp.

Let's see!...................................

Many thanks as always,
Jon

 

It makes perfect sense that the nav is the issue - the nav adds an additional audio source to the stock one, so its cheapest to put the 'multiplexer' between radio-head and nav in the optional equipement - keeps the cost of stock vehicle down and moves the cost to the option. No sense having multiple inputs in the amp, where most users (those without nav) would be paying for unnecessary hardware.

From all we've been through here, I'm about 99.9% certain that the fault is in the head-unit input circuitry inside the nav unit, prior to 'multiplexer' - the switch in the nav unit that selects head or nav as the source to send to the amp. AND, since it's affecting both channels of audio, it's likely someplace where a component is shared, such as a transistor or resistor used in the multiplexing circuitry - a 'select' signal... to turn on the head based audio... TMI?

Good luck - I'd bet this month's paycheck you won't have the noise issue with your current configuration (Nav out of the loop).

Of course, I HAVE been wrong before.... I just can't remember when.

 

@QuadManiac:

I won't make you send me your paycheck this month, but thanks for the offer.

If I did not experience this myself, I might not believe it--but here is what happened now: The problem still exists. Read on to find out something even more surprising.

To recap: I removed the DIN-like AI-Net male connector from the Nav unit going into my Amp and let it dangle free. I then removed the DIN-like AI-Net male connector going into the Nav unit from the Head Unit and plugged it into the now-vacated female connection on the Amp. I therefore tool the Nav unit entirely out of the AI-Net wiring scheme.

Not only did doing this make NO CHANGE WHATSOEVER to the functionality of my system, but also the "white noise" sound still appears as before after about 10 minutes of Head Unit use. The Nav system remained FULLY FUNCTIONAL and to my utter shock--the Nav audio also worked as before (and continued to work even when the Head Unit's audio was fully degraded into that "white noise"). The shock for me is that I expect that the Nav would still display information on the Head Unit and would still navigate properly--but that without the AI-Net cable from the Nav unit, I expected that I would hear no voice prompts from the Nav system. But I was wrong--I still heard them clear-as-day.

I was so shocked that I went back to the truck to ensure that the cables hadn't somehow reattached themselves back to the old configuration!!! (To my relief, they hadn't. )

So, it seems that in the original configuration, the AI-Net cable from the Head Unit to the Nav and then from the Nav to the Amp is simply a PASS-THROUGH. It appears that the Nav is doing nothing AI-Net-wise to the information carried by that AI-Net cable. (This makes me question why it connects to the Nav unit--unless that was somehow to future-proof the wiring architecture.)

I'm a little baffled still... It seems that the AI-Net cables are not involved in the issue and that I should focus more on the Molex-like connectors going to the Amp--as well as the audio information they carry. In other words, it now appears that the Amp is the culprit and not the Nav unit.

I'm glad you allowed a 0.01% escape route... Now what do you think?

Thanks again...

Regards,
Jon