Since the day I got the car, radio/cd player was not working. I am not particularly suffering from not having working stereo (I usually drive with windows down anyway), but I was just curious what is wrong with it. And having nothing better to do at the moment, I decided to jump in it...

The unit that had been installed (by PO or PPO) is JVC KD-SX650. It is a radio + CD player.

I took it out and saw a colorful spaghetti of wires going into two plastic connectors. I have no idea if whoever installed the player did correctly, but I assume that it worked at some point. Well, it is not working now...

First question: is it the player itself or is the problem down the line?

My first test was to trace the connectors for the yellow and black wires on the player and apply 12V from a battery to it. The player did not 'turn on"

I knew that it would not play anything because speaker wires were not connected, but I thought that simply applying 12V to yellow (+) and black (-) connectors would at least turn on the internal lights inside the player and it would show me something on the display. Or is the design of these things not to turn on unless all required wires are connected?

Another question. Is there a fuse in the fuse box that is specific to the radio/stereo? Where is it?

 

Collected a bit more info.

I disconnected Jaguar connectors (white/yellowish ones) and tested for voltage on the inbound 2x3 connector which I assume is coming from the harness (or close to it) somewhere.

With key in the ignition, I am getting steady 12V at the two pins as shown on the picture below. The one in the corner is the yellow wire (hot wire). The one below is much darker color, could not see clearly. The other three pins (one is empty) in 2x3 connector had zero (or almost zero) volts on them.

Does anybody have a detailed electrical diagram for both of these connectors (2x3 and 3x3)? What each pin represents and where do they lead?

I assume the 3x3 connector is for the speakers? (This is my guess based on a spaghetti of thinner wires that were coming from it to the player's connector.)

Given that my player appears to have died, I would need to get another on, but I would need to know how to wire it properly (as it will likely be a different brand/model).

 

I think I know why old JVC stereo died. I decided to open it up and disassemble, out of curiosity, and found one corner of the circuit board damaged/fried/oxydated. See the picture:



No wonder it was not doing anything!

Apologies for asking again about electrical diagram corresponding to the two Jaguar connectors, 2x3 and 3x3, as seen in the picture in my previous post.

Does anybody know where each of the pins is leading to and/or what they mean? Will need this info for wiring the new stereo

 

I attach two documents that deal with how the XJS 1985 original loom connects to a modern DIN speaker plug, they may help.

 

Many many thanks, Greg!

This is a start. I will try to pull the internal (Jaguar) connectors further out and untangle the bundle of wires behind them so that I can better distinguish the colors and the stripes and go from there

 

An update. I got a replacement stereo/radio and am starting working on rewiring.

I studied the write-ups Greg shared:

on UK spec V12 HE cars pre-1987, the radio has:
1. Pink/white feed via a 2 amp fuse just behind the radio, ignition activated,
2. Pink/white 12v wire FROM the radio to the aerial relay to trigger that relay when the radio is switched on
3. Four speakers with 2 wires to each,
4. One purple wire giving 12v continuous feed for the radio memory, fused from the cigar lighter fuse,
5. One grey/red wire that provides radio illumination when the sidelights are switched on.

and tried to carefully compare to what I see in my car ('85 V12 HE, US version), while testing with multimeter. I think I identified all but #2 ("wire from the radio to the aerial relay") from the list above. (Please note that colors of wires in US cars appear to be different from those described in the write up for UK car. So I could not rely on the colors for identification.) See the picture below with labels added.

There are two possibilities: labeled with '?' on the picture.

How do I test which one of them is the wire to the aerial relay? By the way, what is "aerial relay"? What does it do and where is it located? Is it the relay that is supposed to energize the antenna motor to extend the antenna?

 

Can you post a shot of the back of the loom plug showing the wire colours?
You seem to have three 12v feeds. The one that goes live when the lights are on is the radio panel illumination. Of the two others, which are live ignition on and live ignition off?

That brown wire you say is ground (Earth). Is that a loom wire, as normally in Jaguars brown is 12 volt positive, and earth wires (ground wires) are black.

 

Yes, sure. I took pictures of the back, too. From different angles, to see wire colors better. See below.

The yellow and black feeds is where I get 12V with ignition ON. (I thought that one one of them would give me 12V even with ignition OFF, to feed the stereo memory when car is not running. But, no, I only get 12V with ignition on. When the key is not in ignition, I get 0V, nada, on both yellow and black wires.)

The red/white wire in the opposite corner is getting 12V *only* when I turn headlights ON (otherwise it shows 0V). This is the one, I figured, to control radio illumination during night time. (As Greg also indicated.)

There are two more wires -- white and red -- that appear to get 0V in my tests. I assume one of them is for the "aerial relay". But how do I know which one?





Also, I assumed that the "light brown" wire is ground wire because it was connected to a radio wire labeled "ground". But the whole setup was apparently screwed by whoever tried to do it before me. Now I am not so sure anymore

 

Are those white-ish plugs aftermarket or Jaguar ones? If you trace the wires back down the loom, what do they connect to and what colours? The memory always-live 12 v circuit is fused with a line fuse, are you sure this is not blown/have you found it?
The black and yellow colours on the white plugs do not seem to me to be Jaguar ones, as black never carries 12v. If you can, work back down the loom and look for original colours. On your first post, that black plug seems to have the Jaguar wire colours.

 

You mean the white (with a hint of yellow) plastic connectors? Yes, I think they are Jaguar’s original. I found exact same connectors when pulling Radio/CD changer from the donor car (which is ‘86 MY). Which actually reminded me that I should go and check wires and colors and test them for voltage in the donor car, to compare with ‘85. I just need to find a battery to put back in, as I removed it a while ago and drained all the fluids.

I will also try to trace the wires farther back inside and look for the inline fuse. Thanks for the advice!

 

If those yellow and black wires come out of the loom wrapping, then they probably are Jaguar wires. If so, someone must have a wiring schematic for USA cars.

 

Thanks, Greg

So, does anyone has radio/stereo wiring schematics for USA (HE) models?