Audi Comfort CAN

Okay, so, after having some issues with reading the CAN bus without the radio connected, I've now figured it out.

I'm disconnecting the CAN line at the MiniISO connector, and then I only see one signal on the bus, which is ID 428. These, along with another one, specifically ID 439, appear to be used to identify the radio.
If you send the correct values to these IDs, then all the remaining IDs will suddenly reappear.

271 Ignition.
351 siblings.
353 RPM.
621?
623? (Counter... Time...) Operating hours ... unknown.
627?
635 lights, or instrument lighting.
653?

661 activates the upper third of the FIS.

261 top row in the FIS.
263 rows in the bottom section of the FIS system.


Therefore, I would have the possibility of using the FIS to display values. At the same time, I would also like information about speed, RPM, light, and ignition timing.

Now the question arises whether it would be more sensible to connect the adapter to the motor CAN bus and then use the values in the CarPC software. But then I wouldn't be able to use the FIS in the upper part anymore...
So, the only option left is to leave it as is and read things like voltage, boost pressure, oil temperature, etc., either through a relay card or via OBD2... or, alternatively, to use a second [device/system]. Using a CAN adapter...


What do you think about it?

Hello TTron,

We are in the same boat .
I also plan to display the boost pressure, intake air temperature, oil temperature, and oil pressure on the FIS (driver information system).

But surely at least some of the data had to be transmitted on that CAN bus, right? (e.g., oil temperature, oil pressure).


Okay, so I hope my CAN interface arrives soon so I can start working on it.


Regards,

Eddy.

Based on what I can assess at the moment, none of the values are available on the ComfortCAN. I'm not sure which car you're driving, but for my TT, there's a list of values that can also be displayed via the climate control system. Among other things, there are various temperature readings related to the ventilation/heating system, speed and RPM, outside temperature, engine temperature, etc., but there are no oil temperature or boost pressure readings, or anything of that nature.

I think this can only be done via the Motor CAN.

Hello,

I drive an A4 Avant 1.8T, manufactured in November 2002.

You might be right.
I don't have the circuit diagrams in my head right now. Could it be that this data will then be available on the Comfort CAN?
Is the AI likely also connected via the MotorCAN bus?
There has to be some way to connect additional instruments.
ala RS4.

Regards,

Eddy.

I don't have the wiring diagrams memorized right now... I think I was a bit tired when I wrote that. As far as I remember, the climate control system is also connected to the engine CAN bus.




Additional RS4 instruments? Do you have any pictures of that?

Hello Tron,

"No, unfortunately, I don't have any pictures."
If I think about it carefully, it's possible that...
There were no standard features included.
Unfortunately, I no longer have any contact with that person.
He used to drive an RS4.

I received my CAN interface, but unfortunately, I don't have time for it right now.
to try it out, or, currently, it's too cold to work on the car anyway .

Regards,

Eddy.

Sure... it's too cold for me too *g*... also, I think it's a shame that there's not much going on here .
You can't even work 'theoretically' *g*.

Besides comfort, engine, and infotainment, there's also the diagnostic CAN bus (between the OBD connector and the instrument cluster) – at least in the A4 B6. I once read somewhere that it's responsible for communication with the other buses. I can't try that right now, but it might be worth a shot.

What does the abbreviation AI stand for?
I was already able to successfully access the infotainment CAN bus on the radio. However, I haven't had any success with the diagnostic connector (diagnostic CAN?). I would also like to be able to monitor all the buses using an adapter.

Okay, so... it won't be possible to tap into *all* the CAN buses simultaneously, because they operate at different speeds. I haven't tried tapping into the CAN bus at the diagnostic connector yet, but I'll get around to it as soon as the weather improves. What speeds did you try?

AI = Combination Instrument...

All the possible speeds that can be configured in the CAN-Hacker. I even sent the adapter to Fuchs for verification.
Now it's running on the infotainment system.
I suspect that we need to somehow tell the diagnostic interface which bus to communicate with.

Hello everyone,

I would like to revisit this topic, as I am also just starting to explore CAN communication in the infotainment area.

In addition to the information mentioned above, I have also found the following. Perhaps someone can confirm this.

623h: Time/date format '00 hh mm ss tt mm jj jj', as displayed on the combination instrument.

261h/263h are the top two lines in the instrument cluster (IC), and they change depending on the radio/navigation system. I once tried to write something to that address, but I wasn't very successful. Did anyone else have more luck here?

'661h indicates the mode in which the radio/navigation system is operating (FM/AM/LW/CD/MP3/TV).' However, it cannot be switched off by writing to this address.

602h activates TV mode when a specific message is written.

Regards,
Sure, here is the translation of the text from German to English:

'Dirk'

If you've read this entire thread, you'll have noticed that I also have some of the same IDs.

261 + 263 for the two lines in the AI (presumably referring to diagnostic codes), which I can easily describe. However, I no longer have a radio or navigation system connected. When the radio was connected, I had a problem where the radio would immediately overwrite my values. It seems there are still some bits that need to have a specific value so that the AI knows which message has higher priority.

It was intended to be more than just a confirmation. I've already tried it in the car, and it works quite well there too.
I either need to block the 261/263 messages from the radio or send my own message every 50ms, otherwise the radio will overwrite my text. Do you perhaps have the code table that is being used? I've tried experimenting a bit, but it doesn't seem to be ASCII. It also appears that lowercase letters are not available.

I need to log what happens when my Bluetooth car kit connects to my phone. Then, for about 2 seconds, 'BT ON' is displayed, and the text on the radio is overwritten. Since bytes 261/263 are not available for the priority, the 'BT ON' signal might be sent using a different ID.

It would also be interesting to know how to describe the middle section of the FIS (Front Information System). I can see it when the navigation system displays the information there, but the format is completely different. 'In CAN Hacker, several lines have the same ID, and I have no idea how to manually replicate this in CAN Hacker.'

Ah yes, 271 is the ignition.
271 1 10 key not in
271 1 11 key in
271 1 01 key in position 1, ignition off.
271 1 05 key in position 2, ignition off.
271 1 07 key in position 3, ignition on.
271 1 0B key in position 4, ignition on, starter turns.

635 3 xx xx xx Dimming, the first byte is 58d, dimming percentage, 00 = 100% dimmed.

5C3 2 xx xx The buttons on the multifunction steering wheel.

Well, time will tell, or as the saying goes...

So, in my opinion, the middle section cannot be used so easily, as it seems to be controlled by the motor controller... at least, that's what I believe.
'Every 50ms... yes, that's roughly what it could be. It's similar when there's no radio connected. In that case, you also have to send the activation byte every 50ms for the display to stay on. If I'm informed correctly, the individual byte at the beginning (271 1 10 key not in), specifically the '1', represents a kind of value.' That means the data with the higher permission level will be displayed.

As far as the code table is concerned, I believe it refers to the ASCII table for uppercase letters and numbers. No lowercase letters allowed!

I highly doubt it's using the Motor CAN. The Navigation Plus is only connected to the head-up display (HUD) via the infotainment CAN bus, using the middle section. As it appears, the HUD has a pre-defined set of graphics that the navigation system simply calls up. There's also supposed to be a pixel mode where each pixel can be controlled individually. But finding that out probably requires more effort.

271 1 10 means ID 271, length 1, data 10, so it has nothing to do with weighting.