Broken radio/nav system.

[Sunderas]

Hi all.

I have an 09 C5 with the navigation system/radio. A couple of days ago the screen went black and the radio no longer works.
I assumed it was an electrical fault and dived into the car's manual only to find out that there is no mention of any fuse for the radio (like my old Fiesta had) and so I went through all of them. All fuses are perfect, even those in the engine bay.
It dawned on me (due to previous experience) that the radio itself might contain its own fuse.

Can anyone let me know what are the keys I need to use to remove it? Can anyone let me know if they have ever found a similar problem?

Thank you all.


Kind regards

[GiveMeABreak]

I'll need your VIN to determine exact system and specs. Post it here not in a PM please (it will be masked on submission).

[Sunderas]

I'll get it for you tomorrow.

[Sunderas]

I'll need your VIN to determine exact system and specs. Post it here not in a PM please (it will be masked on submission).

VF7**************[VIN obfuscated, can be read by forum staff]

[GiveMeABreak]

Ok, so you have the same system as me, the NG4 Navidrive 3D system.

There is a fuse on the back of the unit (15A blue). You will need these keys to remove the unit:

it is very heavy and so don't allow the unit to pull on the connectors at the back - there are 7 used connections. The fuse is highlighted in white on the diagram below.

Warning: I highly recommend you disconnect the battery first (follow battery disconnect / reconnect procedure) before pulling any connectors off the back of the NG4. This is because the unit is always on and controlled by the network. Always allow the NG4 to finish cooling before removing power and always the remove the Quadlock connector FIRST as this contains the power. The Quadlock should ALWAYS be the last to be connected back afterwards. Never remove the screen display connector (top connector circled in orange) with the quadlock attached as this can damage the screen.

If you suspect problems with it, do a BSI reset first and allow plenty of time before and after the battery disconnect. Sometimes a weak battery or a battery with a low charge can affect the unit.

If you have a Lexia with Diagbox - there are plenty of error codes that the NG4 is capable of returning - so that may help also.

After you have performed a BSI reset and or recharged the car battery, let me know what, if anything happens on the screen when you have connected everything back up and started the car.

If it is still blank, does the screen display parking assistance visuals?

[Sunderas]

First of all, thank you for replying so fast.

I've just ordered the keys from ebay and should be with me in a couple of days.

I can see from the picture you've sent that there are a ton of connectors, but I'll try to go over your instructions so I got it right.

1 - Disconnect the battery. You mention a procedure. Would you please be able to let me know which is it? And the reconnect as well?
Never thought about a procedure with my previous cars. It was just disconnecting the terminals and that was it.

2 - About letting the unit cool. I am doing this before I use the car so I assume this will be fine unless you mean to wait until all energy has been drained.

3 - I assume the quadlock is the one that goes into the connector you highlighted in purple. As for the screen connector (not that I intend on removing it), I should have no problem as the battery will be out of the equation.

4 - If all fails, do a BSI reset. Once more I need to ask for your generosity and request the instructions for it.


Thank you once more for your time.

[GiveMeABreak]

1 - Disconnect the battery. You mention a procedure. Would you please be able to let me know which is it? And the reconnect as well?
Never thought about a procedure with my previous cars. It was just disconnecting the terminals and that was it.

I'll answer questions 1 & 4 together as it is essentially the same thing:-
Think of modern cars as computers. The BSI is a controlling master computer that communicates with the other ECUs on the vehicle via different data networks. The data networks work at different speeds and are split to work with powertrain systems, critical systems and comfort / convenience systems for example. The BSI will send requests or commands to the other ECUs and those ECUs decode the signal to determine if the message is for itself and will send the message on to the other ECUs in the circuit. So when you switch the ignition off, the BSI asks certain ECUs to write their data to memory (like fuel information, miles travelled on current trip, road conditions (suspension), etc. etc., and things like the Head Unit fans will carry on working for a while to ensure the system is cooled. So imagine if you switch the car off and disconnect the battery without allowing time for all the data to be written back... This can cause some of the ECUs to not shut down properly or to write their data correctly. This can cause electrical glitches and / or cause an ECU to get 'stuck' in a state.

This is why the manufacturer states that time should be allowed for ECUs to 'sleep' and also to 'wake up' before and after the battery is disconnected. It's similar to a computer - you would not normally pull the power from the socket without shutting it down first! The times are important too, as when you switch the ignition off, the car data networks are still active. So when we do a battery disconnect, we open the bonnet (to get access to the battery), open a window for access, but then shut all the doors and wait for the car's ECUs to go into sleep mode. Pressing a button or opening the door at anytime will re-awaken the networks. The car has to be able to detect when a door is unlocked or opened so it can start the suspension pump for example, and get the other ECUs powered up in anticipation of the car starting. We don't want this to happen while we are trying to ensure everything is shut down, so we can safely disconnect the battery negative.

Procedure:

• Open bonnet and driver's side window.
• Ensure all doors are closed and remove key from the ignition (do not leave the key in the ignition as the transponder circuit will detect the key and this can prevent the networks from sleeping).
• Wait for 5 minutes, - Don't press any buttons, open any doors or use the remote key fob during this time.
• Disconnect the vehicle battery negative lead and do NOT let it reattach or touch the battery negative terminal post again (use some cloth or other non-conductive material as a barrier). If it touches, the whole process needs to be repeated as you have effectively started the wake up procedure if it touches the terminal.
  
  A) If applicable, now undertake any work or operations you are planning that needs the battery disconnected, OR:
  B) If just resetting the BSI, wait 5 minutes whilst the negative terminal is disconnected.
  
  Reconnection:
• Ensure all doors and tailgate are shut (if you have been doing any work on the car).
• Reconnect the vehicle battery.
• Wait a further 3 minutes (do not open doors).
• Switch on the side lights through the driver's window.
• Switch on the ignition only, don’t start vehicle yet and check ignition lights come on.
• With key still in ignition hold lock button on key down for 5 seconds (to synchronise the remote fob).
• Switch off ignition, remove key through window, then operate Central locking several times.
• Now open door, start the engine and check there are no errors etc.
• Failure to follow this procedure could result in incorrect operation of many BSI related items.

2 - About letting the unit cool. I am doing this before I use the car so I assume this will be fine unless you mean to wait until all energy has been drained.

I just meant that the NG4 has a Hard Drive inside and a cooling fan, so it is important that the unit is allowed to be cooled after a journey. When you switch the car off, the fan will continue to run for several minutes to assist in cooling the device - so another reason to wait before any disconnection of the battery - to allow this.

3 - I assume the quadlock is the one that goes into the connector you highlighted in purple. As for the screen connector (not that I intend on removing it), I should have no problem as the battery will be out of the equation.

Correct

4 - If all fails, do a BSI reset. Once more I need to ask for your generosity and request the instructions for it.

See point 1