That pesky C5 X7 radio again!

[Peter.N.]

Hi Colin

You would be very welcome if and when the situation arises or even if it doesn't! At the moment I have found that there is no ignition switched 12v supply to the radio at present so am in the process of investigating that but with apparently no circuit diagrams available its making things difficult.

Peter

[Peter.N.]

Radio No 96647951ZD. I have at great expense procured a replacement head unit, I excitedly connected it up only to be presented with the same symptoms as before. No radio or satnav and a blank screen. On "normal" radios there is a red and a yellow lead for the power in, this one has a yellow which is permanently live as normal but the red lead which looks pink to me (ignition switched) and also has a push connector on it, has no voltage at all. I have checked and changed F8 which is labelled 'radio' and its OK of course.

I have tried feeding it with 12v from the yellow lead the only difference it makes is that you get a fleeting white bar on the screen when you turn the radio on and off. Have I missed something? I can't really believe that the new radio has the same fault as the old one.

Where do I go from here?

Thanks

Peter

[GiveMeABreak]

Have you considered that your screen may be faulty Peter? The screen is actually supplied by the RT4 via the quadlock connector (Part A 16 Track) on Pin 9 for the supply and the earth on Pin 15. It would be unlikely for 2 failed RT4 - units unless faulty, so it maybe that your screen is playing up especially given what you have said about the white streak. A word of caution here, always disconnect the quadlock connector first and reconnect last before unplugging any other connectors, especially the LVDS cable (top left in the picture) as this can damage the display. The LVDS is low voltage high speed to carry signals back and forth and is very sensitive.

"a" LVDS cable connector.
"b" 3-part connector.
"c" Connector USB (Unused: Service).
"d" GPS aerial .
"e" GSM aerial.
"f" Aerial FM2.
"g" Aerial FM1/AM.

"b" 3-part connector or Quadlock Connector.

Part "A" : Matching the 16 tracks

Channel n° Designation

1 signal: Speaker (RH rear)

2 signal: Speaker (Right hand front)

3 signal: Speaker (Left hand front)

4 signal: Speaker (Left hand rear)

5 Earth: Speaker (RH rear)

6 Earth: Speaker (Right hand front)

7 Earth: Speaker (Left hand front)

8 Earth: Speaker (Left hand rear)

9 Supply: multifunction screen

10 Comfort CAN High

11 Not connected

12 Battery supply

13 Comfort CAN Low

14 Not connected

15 Earth: multifunction screen

16 Earth

Part "B" : Matching the 12 tracks

Channel n° Designation

1 Video input no 1 +

2 Output - Telephone loudspeaker for emergency call

3 Microphone input

4 Input: Audio video socket (Right hand )

5 Screen backlighting signal

6 Video input no 2 + (If connected)

7 Video input no 1 -

8 Output + Telephone loudspeaker for emergency call

9 Supply: Microphone

10 Input: Audio video socket (Left hand )

11 Reference signal: Audio video socket

12 Video input no 2 - (If connected)

Part "C" : Matching the 12 tracks

Channel n° Designation

1 Earth: CD player

2 CAN Low CD changer

3 Power supply through the RT4 of the CD changer

4 CD changer right-hand audio

5 Not connected

6 CAN High steering wheel with fixed central controls control

7 CAN High CD changer

8 Reference signal: CD player

9 Audio amplifier mute

10 CD changer left-hand audio

11 CAN Low steering wheel with fixed central controls control

12 Emergency call request coming from the air bag ECU

[Peter.N.]

Thanks for all that info Marc, at least I have something to work on. Would a faulty display also prevent the radio and parking sensors from working? I didn't realise that it would affect them.

The dark streak down the screen does seem to be getting worse.

Peter

[GiveMeABreak]

It will very likely affect correct operation if it cannot display the information or interpret the data Peter.

The original PSA part was 659371 at £755.21
The is now a replacement part, 6593Q4 at £1278.29

You may be able to source a second hand one by using these or the longer number on the back of the display screen.

[Peter.N.]

Hi Marc

I have fitted a secondhand display and its still as dead as a doornail, no voltage on the red/pink lead. Now where do I go.?

I also have another electronic problem with the other one. During lockdown not being used much it sometimes wouldn't start or did start but died after a couple of hundred yards, I eventually found it was the quick release fitting on the feed to the HP pump leaking air, had to dismantle half the engine to get to it. Couldn't get the correct connector so I fitted a length of 10mm fuel line to the boss on the pump and connected it to the existing pipe further back. Worked perfectly after that.

My son borrowed it the other day and said it would only do a couple of hundred yards and the stop, thought it was a related fault but no, the pump bulb goes hard and there is no loss of fuel. What happens now is that the engine will start but after 15-30 seconds it stops, jus as if switched off, no air and pump bulb hard. Will not start again unless you turn the ignition of and wait until it all shuts down, it will then start but stops again, before it stops it gives a couple of hiccups runs for a few more seconds then stops dead again. repeat the procedure and it starts again. If you remove the MAF plug it makes it worse.

I already have grey hair - it will be falling out soon.

Peter

[GiveMeABreak]

Hi Marc

I have fitted a second hand display and its still as dead as a doornail, no voltage on the red/pink lead. Now where do I go?

Then there is something else going on Peter that I'm not going to be able to fathom on a Forum. If the replacement screen is known to be working and the RT4 is known to be working then it could be a CAN or electrical issue. If the RT4 is faulty, it may not be sending a signal to the display screen. I think you've mentioned previously that you have changed the RT4 already, so if that is the case, then there must be something going on with the connections or the wiring.

As for the other engine-related issues, I'd create a separate topic for those.

[Peter.N.]

Yes I will do that Marc. Presumably a lexica would help diagnose these problems, I will have to see if I can find one that's ready to go, I nearly had a nervous breakdown trying to program the last one. 8-

Have been running Citroens since the '80s, these make the XM's seem simple. I think my next car will be a Morris Minor

Thanks for your help anyway Marc.

Peter

[mickthemaverick]

Peter, Gibbo has a lexia up for sale, may be worth sending him a PM

[Peter.N.]

Just saw it in 'for sale' Mick but he is not selling the laptop with it, I want one that's set up and ready to go. Thanks anyway.

I will probably have to get hold of my friend Colin in Poole.

Peter

[GiveMeABreak]

Peter

Check the mains power (Pin D12) on wire B08A which goes to the BSI and is Fuse F8. I would suggest replacing the fuse in case it has a dry crack that you can't see. It is s 20A and supplies the Audio System the Display, the optional CD Multi changer, Deflation Detection and Motorised tailgate.

[Peter.N.]

Thanks for that Marc, useful diagram, I had part of it but not the whole page, I'm trying to get a decent sized print of it, failed so far will try again tomorrow. I took the fuse out and tested it but it read zero ohms and buzzed the continuity tester.

Peter

[GiveMeABreak]

The image I posted above is a vector graphic, which basically means it will rescale without loss of resolution regardless of image size, however, with the other posts on this page, your printer may of course fit everything else on the page. So I will link the image in a private message for you Peter, where you only have the one post, so it should give you a larger printout.

[Peter.N.]

Thanks for all the info you sent, its been a great help and has enabled me to identify the relevant parts on the French manual. It would seem that the supply for the radio come via BS11 which is the fuse panel containing F8 which I believe is part of the BSI system, there is voltage going in but none coming out. Is replacement of that board possible and economical, there are some available but every one seems to have a different number, or do I have to change the whole system? Most importantly am I liable to disable the car by delving into that?

Thanks again

Peter

[GiveMeABreak]

The BSI is the main brain of the vehicle, so care should be exercised Peter.

There is one other important check you should make before doing anything else in light of your recent post above:

It is possible that the SHUNT fuse has been located in the incorrect position for normal operation - in other words left in park mode for long term storage which disables certain electrical outputs to maintain the battery. If this has been pulled out at some point for checking and reinserted in the wrong location then that is likely to be your problem as the shunt park position will shut off power from the maxi fuse supplying power to F8 from the Engine Fuse Box. This may account for why there is no output from fuse F8.

You therefore need to double check the Shunt fuse is in the client / customer position.

Your BSI may be one of 2 fitted - Here is the diagram for both types and the relevant Shunt Positions:

It is important before removing and replacing the SHUNT fuse to follow the guidance:

The shunt positions below will depend on the layout of your BSI as per the diagram above.

• Switch off the ignition
• Wait 2 minutes for the BSI to switch to standby (don't open any doors or press any switches during this time)
• Remove the flap to access the fuses
• Remove the shunt from the park position ("a" or "c")
• Place the shunt in the customer position ("b" or "d")
• Press the shunt further in, to force it fully into its housing
• Refit the fuse access flap
• Check that the fuse access flap is flush