NazarKmet

Hi. how are you. When I traing to Wakeup Test I getting message For this test ring must be open, What kind of ring we are talking about? How to do it right? Thank you

whoover

The ring is the D2B fiber ring. If you have to ask that question, you're in over your head. As you know, your active fault is "Fault in CAN communication with A40/3n2 (Navigation processor)." You can either take the car to someone with the test equipment and expertise to diagnose the problem and believe him, or you can live with it broken.

NazarKmet

Is it possible to repair this error?

Richard

It depends whats causing it. It could be broken nav processor (bottom bit of the COMAND), broken top bit (i.e the can bus interface in the top bit, or other electronics) or broken wiring between, or just the cable between the two fallen out.

If its the COMAND unit,. MB will say buy a new one (big dosh) - you could try ebay - the COMAND2.5 units are not that expensive as they can only fit in S/CL of certain model years

If its the cable, it should be easy for an auto-electrician to fix.

R

Musikmann

You did not say what problem(s) got you to enter the diagnostic mode in the first place. If you told us that, someone might be able to help you.

Better yet, I would take it to your dealer or trusted independent shop. The COMAND systems are very complicated to work on, and you might make it worse off than it is already.

NazarKmet

I have a problem with Nav. Itn't working I have a B1762 Error. On the forum i got informations to do a D2B Wakeup Test. To see a result. but I can't Thank you.

glassdome

I have a similar problem. I have a 1999 w220 which had an audio 10 and I have retrofitted a comand 2.5. Everything works for the CD, radio, steering controls etc. However, the navigation system does not seem to have any power - I can't insert a CD, and the unit does not make any noise. I have connected all cables, in the E connector with the exception of the following:

1. green wire with a white stripe
2. radio mute wire
3. 2 x black paired wires
4. There is no C1 connector at the moment (TV connector I think)

Any thoughts on the above wires?

Any thoughts on why the navigation section has no power? I am a little concerned it is a faulty unit as I would expect to be able to press the eject button and here cd motor drive noise, or be able to insert a disc.

I too went into the wake up diagnosis mode to check, however, I wonder if:

- the unit is faulty hence no power on
- the car needs to be programmed to say it has navigation so the can bus powers up the navigation part of the comand
- the green wire above needs to be connected to get the unit to power up

Any help would be appreciated as I would really like the navigation unit working.

Thanks in advance.