NG4 Android radio replacement

[Stratoblaster]

I have a 2010 Citroen C5 V6 3.0 Break. It has the original Harman-Becker 2 din head unit and the about 7” display. It has developed a habit to shut itself down after driving some 40-50 km and again and again…

So, I bought a Junsun 10” Android radio replacement. I have now tested it and seems like GPS is working, WIFI is working, BT is working. However I can’t get the audio working.

I began to explore the connections and found out that the 4x2 connection (purple, green, grey, white) that usually carries the speaker signals (FL, FR, RL, RR) and has of course 8 wires coming from the back of the Android radio, connects to a connector that has only four wires? Still the original radio could control left and right as well as front and back because there are 4 speakers.

Then I remembered that there is a subwoofer on the right of the trunk. Ok, the same 4 wires (2 yellowish, orange and grey) attach to the subwoofer unit. My guess is that they must be line level and there is an amplifier (in the box with the sub speaker) delivering the speaker level signals to door speakers. I just wonder how is that done with 4 wires only coming in? I mean how can it handle both panning L and R and Front and Back?

What should I do? Rewire 8 (or at least 4 extra wires if use the existing 4) speaker wires (plus an RCA cable for the sub amp) to the sub box in the back so I can use the power amp of the new Android unit.

The Android unit of course has got RCA-line outs but I don’t know the pinout of the 4 original wires or what kind of signal is it feeding? What would be the easiest way? The Front / Back adjustment is not so necessary if I could only get a L / R signal through.

And one more thing… The steering wheel button support was not working either when test used the Android unit.

Thanks in advance!

See the attached photos.

[GiveMeABreak]

I know a little late now as you've bought it, but you could of just done the CF card replacement of the hard drive and you'd be back to normal most likely, unless there was a hardware fault of course.

It's a different kettle of fish with a) the HiFi Amplifier option and b) if you have the services module fitted, which also uses at least on of the speakers for emergency services connection when airbags have been triggered - along with geolocation in a crash.

That wiring diagram is for an RT4 not an NG4 with HiFi and possible services module.

If you provide your VIN I'll get a wiring diagram up of the NG4 for you. Please post your VIN in full without spaces - it will be automatically masked from public view after submitting your post & will only be visible to staff.

[Stratoblaster]

Yeah, I know that I could have installed a CF-card. I actually ordered an exact replacement Toshiba disk for it if I have to re-install the old system. I guess it is possible without any troubles, re-coding etc?

You mean the VF7**************[VIN obfuscated, can be read by forum staff]… as a VIN?

[Stratoblaster]

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

[GiveMeABreak]

Yes, the only drives I'm aware of apart from new (if you can still get them) are old used ones from old servers and are probably near end of life too!

Here's the HiFi Connections in case it helps.

"a" 16-way blue connector.
"b" 16-way black connector.
"c" Bonnet locking 16.

Note: The speaker cables are twisted in positive and negative pairs and bear the same name.

Role
The audio amplifier amplifies the 4 audio outputs from the audio system and distributes them over 8 amplified outputs:

• 2 outputs for the front woofers
• 2 outputs for the front tweeters
• 2 for the rear tweeters and woofers connected in parallel
• 2 outputs for the bass box

Electrical features
The connection to the audio amplifier is by means of 3 connectors (The 3 connectors are of the SICMA 16-way type):

• The black connector transmits the low power information and the supplies
• The blue connector transmits the power information to the right-hand speakers
• The white connector transmits the power information to the left-hand speakers

"a" 16-way blue connector

Channel number	Designation
1	Front right tweeter +
2	+ front door right-hand bass speaker
3	Unused
4	+ rear door right-hand speaker
5	Unused
6	Right-hand bass module +
7	Unused
8	Right-hand central channel +
9	Front right tweeter -
10	- front door right-hand bass speaker
11	Unused
12	- rear door right-hand speaker
13	Unused
14	Right-hand bass module -
15	Unused
16	Right-hand central channel -

"b" 16-way black connector

Channel number	Designation
1	Unused
2	CAN +
3	Unused
4	Right-hand audio system + input
5	Right-hand audio system - input
6	Unused
7	CAN High
8	Unused
9	Permanent +
10	Unused
11	Left-hand audio system - input
12	Left-hand audio system + input
13	Unused
14	VAN Low
15	Unused
16	Earth

"c" Bonnet locking 16

Channel number	Designation
1	Front left tweeter +
2	+ front door left-hand bass speaker
3	Unused
4	+ rear door left-hand speaker
5	Unused
6	Left-hand bass module +
7	Unused
8	Left-hand central channel +
9	Front left tweeter -
10	- front door left-hand bass speaker
11	Unused
12	- rear door left-hand speaker
13	Unused
14	Left-hand bass module -
15	Unused
16	Left-hand central channel -

[Stratoblaster]

Oh, that is not easy! Where is that box located?

[GiveMeABreak]

On a left hand drive, it's hidden behind the right side (passenger) of the dashboard, so the glovebox need to come off to get access to it.

[Stratoblaster]

Thanks a lot!

If I solder an RCA connector both to pins 4/5 and 11/12 of the black box and feed there a line-out signal from Android unit, should it do the trick? Propably not since the NG4 is not guiding the system anymore? Or is the HiFi amp totally indipendent from the head unit I have disassembled?

[GiveMeABreak]

The HiFi was an optional extra - and NG4 was supplied with and without the amp and with or without the services module.

These are the NG4 Speaker connections:

"e" 3-part connector

Part "A": 16 way connector

Channel number	Allocation of channels of connector
1	signal: Right hand rear speaker
2	signal: Front right hand speaker
3	signal: Front left hand speaker
4	signal: Rear left loudspeaker
5	Earth : Right hand rear speaker
6	Earth : Front right hand speaker
7	Earth : Front left hand speaker
8	Earth : Rear left loudspeaker
9	Supply : Screen DG4
10	Comfort CAN High
11	Channel not allocated
12	Battery + supply
13	Comfort CAN Low
14	Channel not allocated
15	Earth : Screen DG4
16	Earth

Part "B": 12 way connector

Channel number	Allocation of channels of connector
1	Video input no 1 +
2	Channel not allocated
3	Earth : Microphone
4	Right-hand audio auxiliary
5	LIN bus for screen DG4
6	Video input no 2 +
7	Video n°1 -
8	Channel not allocated
9	Input : Microphone signal
10	Left-hand audio auxiliary
11	Audio earth
12	Video n°2 -

Part "C" : 12-way black connector (*)
(*) Only with CD changer (Not available on hybrid vehicles)

Channel number	Allocation of channels of connector
1	Earth : CD changer
2	VAN Low : CD changer
3	Permanent + : CD changer
4	Right audio system: CD changer
5	Rear socket LH audio output signal
6	Channel not allocated
7	CAN High : CD changer
8	Earth : CD changer
9	Rear socket RH audio output signal
10	Left audio system: CD changer
11	Channel not allocated
12	Rear socket audio output earth

[DHallworth]

Sorry to hijack your thread. I might be interested in buying your old NG4 as half of the buttons on the front of mine don't work and the joystick is hanging off. Would be good to make 1 out of the 2.

Let me know if you do decide to sell it please.

David.

[Stratoblaster]

Sorry to hijack your thread. I might be interested in buying your old NG4 as half of the buttons on the front of mine don't work and the joystick is hanging off. Would be good to make 1 out of the 2.

Let me know if you do decide to sell it please.

David.

Sorry but I decided to keep the original unit because it is too complicated to try to replace it with a modern Android unit.

I have now tested how to install the Android unit as a second unit and feed the audio signal from its RCA-outs to the AUX ins of the original unit. It works fine. The new 10” diaplay goes to the place of the old display and the old display goes on top of the dashboard in a housing (which I have to custom build). Sounds easy, eh!

[Stratoblaster]

Is there an ”ignition 12V” somewhere available in those wires that come to the back of the NG4? I need that to wake up the Android unit.

The HiFi was an optional extra - and NG4 was supplied with and without the amp and with or without the services module.

These are the NG4 Speaker connections:



"e" 3-part connector

Part "A": 16 way connector

Channel number	Allocation of channels of connector
1	signal: Right hand rear speaker
2	signal: Front right hand speaker
3	signal: Front left hand speaker
4	signal: Rear left loudspeaker
5	Earth : Right hand rear speaker
6	Earth : Front right hand speaker
7	Earth : Front left hand speaker
8	Earth : Rear left loudspeaker
9	Supply : Screen DG4
10	Comfort CAN High
11	Channel not allocated
12	Battery + supply
13	Comfort CAN Low
14	Channel not allocated
15	Earth : Screen DG4
16	Earth

Part "B": 12 way connector

Channel number	Allocation of channels of connector
1	Video input no 1 +
2	Channel not allocated
3	Earth : Microphone
4	Right-hand audio auxiliary
5	LIN bus for screen DG4
6	Video input no 2 +
7	Video n°1 -
8	Channel not allocated
9	Input : Microphone signal
10	Left-hand audio auxiliary
11	Audio earth
12	Video n°2 -

Part "C" : 12-way black connector (*)
(*) Only with CD changer (Not available on hybrid vehicles)

Channel number	Allocation of channels of connector
1	Earth : CD changer
2	VAN Low : CD changer
3	Permanent + : CD changer
4	Right audio system: CD changer
5	Rear socket LH audio output signal
6	Channel not allocated
7	CAN High : CD changer
8	Earth : CD changer
9	Rear socket RH audio output signal
10	Left audio system: CD changer
11	Channel not allocated
12	Rear socket audio output earth

[GiveMeABreak]

No, because these original telematics units in the vehicle have to use a permanent live all the time, hence Pin 12 on Part A.

[Kreoshoc]

Ok, you are lucky, because I had the same issue while replacing my NG4 (also with HiFi sound). A head unit fully controls the amplifier: volume is set by the can bus (hu provides a constant level of output), equalizer, balance, and fader - all controlled by can packages sent from the head unit to the amplifier by the can bus. And Chinese can bus adapters don't support that functionality. So the solution is to develop a custom can bus adapter that will push missed or broken can packages into the can bus.

I've developed a can bus adapter based on Arduino, here is a sketch: https://github.com/lozynskiy/citroen_ca ... ceiver.ino and here is described a development process (divided into 3 parts, don't miss them all, please use google translator): https://driver.top/exp/498635/
Also, it allows mapping wheel buttons using the SWC application.

Feel free to ask any questions.

[sonny7]

Ok, you are lucky, because I had the same issue while replacing my NG4 (also with HiFi sound). A head unit fully controls the amplifier: volume is set by the can bus (hu provides a constant level of output), equalizer, balance, and fader - all controlled by can packages sent from the head unit to the amplifier by the can bus. And Chinese can bus adapters don't support that functionality. So the solution is to develop a custom can bus adapter that will push missed or broken can packages into the can bus.

I've developed a can bus adapter based on Arduino, here is a sketch: https://github.com/lozynskiy/citroen_ca ... ceiver.ino and here is described a development process (divided into 3 parts, don't miss them all, please use google translator): https://driver.top/exp/498635/
Also, it allows mapping wheel buttons using the SWC application.

Feel free to ask any questions.

Omg! I'm reading this and it seems that you have exactly explained my problem!!

I have a C5 (X7) with the HiFi option - and therefore the Amp - but it doesn't work with the Junsun chinese unit I bought.
The sound is horrible and does not work with some speakers, if I put the fader all the way to the rear speaker I get not sound at all. I even bought another CanBus "RZ-PSA15" but it's the same thing..

So yeah what you explained seem to solve the problem we would all encounter with these chinese Android units.

However, I'm very very bad with electronics, just fitting that Junsun unit was a big headache for me, so really I don't how I could reprogram a CanBus or something, seems totally impossible to me
But..! there could be a solution, maybe you would be willing to sell that to me?

Just let me know, your help would be welcome
Cheers from Tallinn, Estonia!