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Hi Guys,

I removed the original factory fitted head unit from my 2004 147, it's a 937 CD NSB, with the intention of bench testing it, to try and play with the CDC data in and out pins...

So after buying the din pins to remove the HU and getting my hands on a power supply to power the stereo, I now find I can't get passed the "Cancheck". Any idea's how to get around it?

I have the original security code, but typing it in doesn't do anything (unless I'm doing it wrong, do I need to press any other buttons before or after?) And I tried generating a new code using the program from another thread, no joy there either. I guess the HU needs to be connected to the cars CAN network before the can check will go away...

Does anyone know a way of getting around it, so I can test it indoors?


Thanks for the help!
 

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Hi Guys,

I removed the original factory fitted head unit from my 2004 147, it's a 937 CD NSB, with the intention of bench testing it, to try and play with the CDC data in and out pins...

So after buying the din pins to remove the HU and getting my hands on a power supply to power the stereo, I now find I can't get passed the "Cancheck". Any idea's how to get around it?

I have the original security code, but typing it in doesn't do anything (unless I'm doing it wrong, do I need to press any other buttons before or after?) And I tried generating a new code using the program from another thread, no joy there either. I guess the HU needs to be connected to the cars CAN network before the can check will go away...

Does anyone know a way of getting around it, so I can test it indoors?


Thanks for the help!
First off, the security code is a dialogue between the radio and the bodycomputer, via the CAN bus. So obviously, you cannot succesfully enter a security code when the radio is not connected to the bodycomputer via the CAN bus.
Secondly, you might have some luck using the HU stand-alone if you connect a 12 Volt supply to both ISO A4 and ISO A7 connections....
 

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Discussion Starter #3
Thanks very much JWQ,


From my vague memory though, I don't think there's a pin at position 4 on the socket, or pin 6. I think it's set up like this... althought I'll have a look tonight to make sure.



Pin 1 CAN B
2 Booster In*
3 CAN A
4 not connected
5 AUT. ANT.
6 not connected
7 UB
8 Gnd

When I first tested it, I connected 12V to Pin 7, UB, and ground to ground. Do you think I should connect 12V to any of the other pins?



Appreciate the help!
 

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Thanks very much JWQ,


From my vague memory though, I don't think there's a pin at position 4 on the socket, or pin 6. I think it's set up like this... althought I'll have a look tonight to make sure.



Pin 1 CAN B
2 Booster In*
3 CAN A
4 not connected
5 AUT. ANT.
6 not connected
7 UB
8 Gnd

When I first tested it, I connected 12V to Pin 7, UB, and ground to ground. Do you think I should connect 12V to any of the other pins?



Appreciate the help!
Yep, that's the point..;)
When the HU is connected to the car, it's only connected to the permanent +12 via ISO A7... It get's the switch-on/switch-off signal via the CAN bus.

However, obviously, when it's outside the car it's not going to get a switch-on signal. You can get around this by connecting a switched +12 to ISO A4
So both A4 and A7 should be connected to +12 in case there is no CAN...
:)
 

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Can I just ask what you re gonna try and do with the data, drgonzo?

(And why did you buy a "tool" for removing it when you could just use a couple of small screw drivers?)
 

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Discussion Starter #6
Yep, that's the point..;)
When the HU is connected to the car, it's only connected to the permanent +12 via ISO A7... It get's the switch-on/switch-off signal via the CAN bus.

However, obviously, when it's outside the car it's not going to get a switch-on signal. You can get around this by connecting a switched +12 to ISO A4
So both A4 and A7 should be connected to +12 in case there is no CAN...
:)
Thanks for you quick reply,

I took the stereo back out, there is no pin 4 as we guessed, so I tried shoving a wire in where a pin would be, but don't think it's connecting to anything.... So I pulled the radio apart to get down to the bare PCB and I can't even find a track for where pin 4 would connect to. Do you know if this has been done on this model of stereo?
Or do you know of a location further down on the PCB where I could connect the 12v to? I guess a schematic would help, if one existed...



Typos1, I was optimistically hoping I could some way play around with an arduino I have, (it's a small programable micro controller) to emulate a CD changer and so open the aux audio input for my MP3 player... but it seems to be constant battle, even trying to just turn the thing on in the house is a challenge...



Thanks guys, for your time and help!
 

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I believe that it is a security feature that the stereo needs to talk to the body computer and just won't work without YOUR body computer being present (similar to the Engine ECU and the Imobiliser ECU) ...


tbh for the amount of time/effort you're going to put it wouldn't it just be better to put in a aftermarket system? (it would also be an improvement)
 

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Thanks for you quick reply,

I took the stereo back out, there is no pin 4 as we guessed, so I tried shoving a wire in where a pin would be, but don't think it's connecting to anything.... So I pulled the radio apart to get down to the bare PCB and I can't even find a track for where pin 4 would connect to. Do you know if this has been done on this model of stereo?
Or do you know of a location further down on the PCB where I could connect the 12v to? I guess a schematic would help, if one existed...
I had a quick look at the schematics, and unfortunately you're right, contrary to f.i. the connect nav, the radio does not support a switched +12 ....
 

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I thought thats what you might want drgonzo.

I thought that 937 was the standard non Connect HU? Although never heard of "NSB". You can get the latest Connects2 interface for it and that does the job for you, its got an SD slot, a USB port and a miniUSB port for bluetooth in. The new version looks exactly like the Bluebrird thing that was available a while back. Only about £55

I ve got Connect and it recognises it as a cdc but wont play anything.

If you want audio in you can get it by adding a wire, there are instructions on here somewhere
 

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Discussion Starter #10
I believe that it is a security feature that the stereo needs to talk to the body computer and just won't work without YOUR body computer being present (similar to the Engine ECU and the Imobiliser ECU) ...


tbh for the amount of time/effort you're going to put it wouldn't it just be better to put in a aftermarket system? (it would also be an improvement)

I'm begining to think you're right...
I like what you've done with with your carputer. Was it a big job making a PC communicate with the car's CAN network?



I had a quick look at the schematics, and unfortunately you're right, contrary to f.i. the connect nav, the radio does not support a switched +12 ....

Thanks for checking that out!
Are the schematics you have in the publin domain? If so, I'd be keen to have a peek at them. Is there any mention of the communication protocal used by the CD changer?

I thought thats what you might want drgonzo.

I thought that 937 was the standard non Connect HU? Although never heard of "NSB". You can get the latest Connects2 interface for it and that does the job for you, its got an SD slot, a USB port and a miniUSB port for bluetooth in. The new version looks exactly like the Bluebrird thing that was available a while back. Only about £55

I ve got Connect and it recognises it as a cdc but wont play anything.

If you want audio in you can get it by adding a wire, there are instructions on here somewhere
Thanks for the advice...
Yes, it seems there were older versions of firmware where you could just jumper the data in and data out pins - which would open the audio in.. but seems this stopped working on later versions. Blaupunkt went well out of their way to make these stereos un-modifable by your average person it would seem...

Maybe I'll play around with it some more when the weather warms up and I can sit in the car with my laptop...


Have a nice weekend guys!
 
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