Benz and Jag D2B systems not compatible
 

I've been looking into the D2B optical system for some time and wanted to see if the Jag and MB share the same system.

I had some hope since the CD-changer units look really similar - an thy are. They use the same magazine and almost all HW is identical. Both units have a small real block that contains the optical transmitter unit.

The Benz and Jag have different optical connectors, but I was wondering if I can swap the optical transmitter board. Well yes you can - but it does not help.

Both optical transmitter boards have the same interface to the main unit - 17 pin FPC cable (1mm pin pitch). Both boards have the same electrical signals on the connector.

However there is some difference in the software for both units. The Jag changer would initialize the D2B address and respond to basic commands (like ping and power off), but it would not recognize most of the other commands from the Benz HU.

So if you were thinking of getting a Dension GW 500 Benz unit - it will not work in your Jag even if you somehow manage to retrofit it in the optical system.

Some pictures of the optical transmitter from the Jag and MB for your viewing pleasure. The Jag unit is the board with the black housing. The open board is from MB CD-changer.

PS: I reverse engineered the electrical pinout of the transmitter. PM me if you are interested.

Very useful nonetheless @veffremov

You mentioned that the CDC in the Jag wouldn't respond to the Merc HDU, and that's to be expected - as you found out, the firmware is different. That being said L1/L2/L3 interfacing - i.e. the unit connecting and being found is a really good started for ten.

May I have the pinout of the transmitter please ? :)

Thanks.

Sorry took me a while to find the old doc:
https://drive.google.com/file/d/0B9T...da5DY5ZySJHtwA

Optical IO board (contacts up) MC3010
17 pin connector

1 - Fsync (pin 12 of OCC8001)
2 - SCLK (pin 13 of OCC8001)
3 - SR1 (pin 14 of OCC8001)
4 - OCERR (pin 27 of OCC8001)
5 - GND
6 - OCREQ - Optical input AND gate (pin 1 on TC7S08F)
7 - i2c SCL (pin 2 of OCC8001)
8 - i2c SDA (pin 1 of OCC8001)
9 - OCINT (pin 2 of OCC8001)
10 - WAKEUP
11 - OCRESET (pin 23 of OCC8001)
12 - RMCLK (pin 6 of OCC8001)
13 - GND
14 - GND
15 - BAT +12V
16 - BAT +12V
17 - VCC +5V

On MC3198 Contacts are down and connector is flopped (pin 1 = pin 17)

The Fsync/SCLK/SR1 pins are I2S interface for digital audio data. Find the Becker 3100 schematics for details on the wake-up circuit and pin 6.

Note on power: the CDC takes 12V via the 3 pin connector. The 12V is sent to the main CDC unit via pins 15 and 16 of the FPC cable. The main CDC unit has a power regulator and sends back 5V to the transmitter unit via pin 17.

The RMCLK pin is also part of the i2s interface, I forgot to include it in the above message.

The OCREQ is labeled OCCRON on the be 3100 schematics - logic 1 enabled the incoming optical data to be connected to the OCC8001 chip, 0 disables it. Not quite sure what that is used for - maybe diagnostics. Disabling the data would really break the D2B bus.

Veffemov,

Darn you had me going with your investigation of compatibility between Benz and Jag. My 05 CLK just got totalled so driving my 04 XJ8 daily now with touch screen but no BT. I actually have a parts car of the CLK so I have 2 and I'd be willing to make the conversion if they were compatible but apparently they're not. On the CLK it was very easy to add aux input via the CDC and a $75 cable from the dealer. I popped the door sill and located the specific white plastic plug and plugged in my cable and Bada bing Bada boom... Success... Wish the Jag was as simple. Darn.

Veffremov,

Sorry for misspelling your name in post above.

Veffremov,

Sorry for misspelling your name in post above.

Im actually using a Mercedes cdc magazine in my STR because all the jag owners were being jagoffs and trying jag me for it (cheapest one was like $80 for the magazine). So I bought a MB one off ebay for $14

Hey Aarcuda,

So was it simple to convert ? I just got an FM transmitter today to get by in the meantime, but as we all know the radio does not sounds as good as a CD / CDC, aside from the FM transmitter and connection issues.