Citroen C5 X7 head unit issues

[Yuli]

Hello.

I am new in that forum as a member, but have read some topics.

So my C5 head unit stopped recognizing the USB stick from which i was playing music. I have no idea why and what happened. I've tried 3 different USB sticks, all formatted FAT32, tried SD card...nothing happens. I am plugging the USB stick, the SD card - the head unit doesnt react at all. Only radio is playing. Any ideas?

The head unit FW version - ng4_D_N42c_n42.03

Best regards,

Yuli

[GiveMeABreak]

That is the latest and last version of firmware.

If it was USB only, I would suggest your USB device or the number of files on the device, but if you have been using this device successfully already, there may be an internal fault.

This can happen with a USB over voltage situation - specifically if you have plugged in dodgy USB cables into the port (especially cheap Chinese uncertified cables) that can overload the circuit and then you've had it. This is particularly the case with phone chargers! Only use official chargers that have the correct circuitry and voltage protection included in the USB cable. If one of these has damaged the unit, you're stuck I'm afraid.

Just for information, the USB port on the NG4 is USB 2.0 and the maximum number of files is 4000, with 1000 max in each of 4 folders. So make sure you are not exceeding these.

Next tray a BSI Reset / Battery Disconnect / Reconnect Procedure and leave the battery disconnected for 10 minutes, which may reset the NG4. Then try again.

[Yuli]

Hello.

Ive only used the USB drive plugged in directly into the USB port. Never used anything else to plug in the USB port. There are about 200 files in the drive in many folders.

Ive tested the USB port if it is functioning at all with my phone - there is definitely power to the USB port, because its charging the phone.

How everything started - i was driving on the highway and stopped at a gas station to fill up some liquid for the wipers. After i was done, started the car and the USB was not working anymore. After 50 km, the car started to give me error "Engine fault" and kinda stopped (i suspect the DPF was really clogged, because on my way back, DPF regeneration was running like 4 times for 150 km of driving and prior to that, there was an error which was saying the particle filter might get clogged). I pulled out the ignition key and started wondering whats going on. Started the car again and it was running normally with the error still showing. Ive removed the positive end on the battery when i arrived at my destination, waited for 5 min and connected the battery again. The car started working normally without the error (which never showed again), but the USB stick was still not working. When i got home, i formatted the USB and it started working again. After few days the USB stopped working permanently, even after formatting it few times. Just to mention - each time the USB stopped working, the multimedia "lost" its settings, because i had to set the date and time.

Isnt there any fuse which can protect from overvoltage? Ive never checked the fuses by the way. Might also do that.

Will also try the BSI reset later today.

BR,

Yuli

[GiveMeABreak]

Ok, so with this additional information - especially concerning the date and time, that tells me the NG4 unit's backup battery is toast, so is losing configuration.

[Yuli]

Hey.

Is the battery hot swappable? Can i replace it or its somewhere inside the unit?

Yuli

[GiveMeABreak]

If you have the emergency calling buttons / Service call, then you'll likely have the 'Services Module', which is where the backup battery is installed to provide power for Emergency calls / Geo-location in an accident.

[Yuli]

Hey.

I removed the head unit and what i see on the back there is a fuse which i checked and it okay. Where is that service module located? Is is somewhere around the head unit? I do have emergency calling/SOS buttons, but i dont know what should i be looking for regarding the service module.

Thank you.

[GiveMeABreak]

No, the services module is buried deep in the dash - on the right hand side:

If you take the end trim off the dash, you may be able to get access to it - see my post with pictures here: Installing Dash Cam C5 X7

[Yuli]

Thank you.

By the way, the bluetooth takes a lot to initiate, not to mention to connect to my phone. Do you think this has something to do with the music not playing? Also, the SD card slot also does not want to play any music...formatted the SD to FAT32...nothing.

[GiveMeABreak]

You may need to try resetting the unit to factory default, or it may be that the hard disk drive is starting to fail which may be causing some problems. Normally you can play MP3 files using the USB port in the centre console which is where you update the firmware from.

[Yuli]

Hey.

I did try resetting the unit multiple times - no success. The USB is not playing any music, the flash drive isnt even recognized. I tried multiple USB drives. The SD card is also not playing anything. Only radio is working and the bluetooth is initiating really slow. I tried flash drive with a firmware on it, so i can re-flash it - USB is again not recognized.

[GiveMeABreak]

So in this case if you have tried removing the Quadlock and checking the connections, we have to assume it's lost some configuration or worse.

I would suggest as a last attempt that you create a CD-R disc and burn the firmware files onto the CD and then finalise the CD, then try and see if the unit will boot off of that or attempt reininstalling the firmware that way, as the DVD-ROM drive is the master IDE device, so will always attempt to boot from this device first.