Topic: VAGCOM Adapter (again)

Hello VAGCOM community.

Regarding adapters, there is now more information available in the diagnostic technical article, and also a (hopefully useful) universal version 2.2.
Since version 1.x of the "economy" version only works with COM ports that have sufficient current output, and most VAGCOM users likely work with laptops that have weaker specifications, I discontinued development on that line.

"Since I've recently received several direct messages regarding PCB layout:"
I'm unable to provide that, as I lack the necessary expertise – I personally work with universal circuit boards.
I would appreciate it if you would refrain from making any further inquiries.

Conversely, it might be a good idea if someone were to design an etching template that Rainer could make available on his website... ?

Ideally, this should happen after the then-current adapter version has been confirmed to provide stable operation in the majority of clinical reports...


@Rainer: I would like to keep the thread at the top for about a week (hence the "Important" designation) and then change it back to normal, so that too many long-standing threads don't accumulate at the top of the forum.
If I forget, please turn off the "Important" flag (or another moderator can do it).

Okay .

I will probably be able to use a CAD program (Ranger2) tonight and then post it here (let it be posted ).

Hi DaBibo,
If you have it or can work with it, try using Eagle. It's probably more widely used than Ranger. The free version should be sufficient for the adapter.

Best regards, Rudi.

I just crashed, I was almost finished with the circuit diagram.

I find it easier to use features like the autorouter with Ranger.
I can try it, but it will be quite large due to all the resistors .

Hello.
So, I had assembled the adapter, version 2.1, and VAG-COM didn't detect the adapter. LED test was ok.
I used the 1N4004, 2N3904, and PC 817 components for the circuit. That should be fine. What did I do wrong?
The new version should fix that bug, and what function is switch S1 supposed to perform? What would be the appropriate initial setting for the potentiometer adjustments?

Best regards,
Nobody.

Niemand wrote:

Hello. So, I had assembled the adapter, version 2.1, and VAG-COM didn't detect the adapter. LED test was ok. I used the 1N4004, 2N3904, and PC 817 components for the circuit. That should be fine. What did I do wrong? The new version should fix that bug, and what function is switch S1 supposed to perform? Regarding the trimpots, what would be an appropriate starting position?

Hi.

What are the results of the dry function test (function check without a PC, as described in the diagnostic article, with S1 open)?

S1 serves to functionally approximate the adapter to the Noxon minimal model.
As a starting position, I would place the pots in the middle.


@all:
My computer has been acting up lately (it often forgets the BIOS despite having a fully charged battery, etc.).
If I don't participate in the forum for a while, it's most likely due to .

Hi,
Here is a case report:
I assembled version 2.2.
He passes the dry tests, but I can only access ABS module 03 in my vehicle (error memory, no blocks due to...). Shareware).
"When I try to access the more important engine control unit (01), I get the message 'can't synch baud rate'."
Ulf (?) already reported about that in version 2.0.
Vehicle: Audi 100, 1992, 2.5L AAT engine. PC: Dell laptop, 266 MHz.
What baud rates does VAG-Com actually test? Could it help to manually adjust an "incorrect" initial value?
Where in the facility should I take measurements and, if necessary, adjust the values to meet the target specifications?

Okay, I manually de-routed the circuit and etched it onto a PCB. If Da Bibo's software keeps crashing, I could also redraw it properly in CAD and post it.

Christian

christians wrote:

Hi, Here is a case report: I assembled version 2.2. He passes the dry tests, but I can only access ABS module 03 in my vehicle (error memory, no blocks due to...). Shareware). "When I try to access the more important engine control unit (01), I get the message 'can't synch baud rate'." Ulf (?) has already reported on this from version 2.0.

Hi Christian,

Yes, that's correct, but since I changed R 10 and 11 to 1 kOhm each and R 9 to 3.3 kOhm (without VR 1 in series / part numbers referring to plan 2.2), my adapter has been communicating stably with the motor and ABS.

I'm hesitant to address the airbags because of the potential for "tipping" the control unit software (a warning in VAGCOM), and I've simply forgotten about the WFS so far...

I bought the Elitegroup "bargain" laptop for €777.

Quote:

Where in the facility would I need to take measurements and, if necessary, adjust settings to meet target values?

Perhaps at the collector of transistor T3 (using an oscilloscope!).
The voltage there should fluctuate rapidly and clearly between approximately 0.3 and 12 volts.
Here, "fast" means having the same slew rate as the K-line when communicating with the ABS.
Ideally, the K-line and the collector of the T3 should be mapped to two separate channels.

Compare the signal waveforms at the collector of transistor T3 during the ABS communication and during the attempt to communicate with the engine control unit. Then, use potentiometers VR1 and VR2 to optimize the signal waveform at the collector of transistor T3.
Good luck .

If you can't find an oscilloscope: Too bad .

Thank you for the new schematic, version 2.2.
'It flawlessly recognizes the airbag and ABS controllers on a T4 4/95 (70XOC) (airbag error produced, successfully reset), even with completely non-critical VR1/VR2 values. The same applies to a Polo 6N 12/94 AEF, where all possible VAG COM functions work immediately, including the diesel pump (41), actuator (03), and measurement block 01. Everything works perfectly from the start.'
At Reichelt, only the 2x and 4x models are available for the PC 829/849 Sharp.

Excellent:D LED diagnostics using VAG COM under Options; this should be mentioned in the description, as description errors in the LED area become very apparent. LEDs 1 & 2 are also tested without supply voltage.
I initially considered the VCC LED to be unnecessary, but since I learned that LEDs 1 & 2 (I used super-bright SLH56 LEDs here, which is the only deviation from the schematic) also light up without VCC, simply through the COM port, it's often not immediately obvious that the power supply is missing, especially in a busy situation.

Everything was tested using an old Compaq Armada and an HP Omnibook 2100. Everything is housed in a probe housing (Bopla, where the probe end can be used as a strain relief), and the connectors are built using a socket (which is often found as scrap). Solder pins are used as contacts. They are now available at Elektor Krüger in Hanover for 12.50 euros including shipping.
The connectors for the K&L Line can be found in older Polos, located in the central electrical system and featuring brown/red wires. The data connector fits perfectly, but you may need to force it into the VCC socket.

A request to the layout designers: Please use the following as a basis: a 4-way OK PC 849 pinout (refer to the diagram here).
http://www.sharp.co.jp/ecg/opto/products/pdf/en/oed/photocouplers/pc829_e.pdf

Thank you again, kai, who no longer has any 1KS.

P.S. Opel software at a VAG-Com price would also be interesting. Is there anything like that available?

I'm also interested in Opel, as my wife unfortunately still drives one of those cars and will have to for a while! Is there anything reasonable and comparable available? I know it's off-topic, so please don't get too upset!

Hi,
Thank you for the response.
I'm going to borrow an Oscar from the company next week.
Hopefully, I'll be a bit wiser by then, and I'll follow up with a report.
Christian

Bringing coals to Newcastle, or stating the obvious.
I have just "discovered" http://e-www.motorola.com/brdata/PDFDB/docs/MC33199.pdf an IC for converting K/L to serial.
At first glance, it looks like a good fit.

Best regards, Christian.

christians wrote:

To risk stating the obvious: I have just "discovered"

an IC for converting K/L to serial.
At first glance, it looks like it fits.

Hi Christian,

An interesting link regarding hardware.

I also had the idea of replacing the discrete transistor stages with comparator ICs (like in the Motorola chip) http://e-www.motorola.com/brdata/PDFDB/docs/MC33199.pdf.

Why all the effort?
Today, I tested your 2.2 on a 1994 Volkswagen Golf TDI. It worked perfectly right away. Interestingly, on this vehicle, the ground connection was not wired in the OBD socket. However, that doesn't matter to me, as I get the power supply from the cigarette lighter socket, which saves me from having to deal with the small connector pair of the old OBD version.
But unlike the original design, your circuit works perfectly, and you can actually obtain all the necessary components, which I doubt is the case with the Motorola version. And – more parts mean more potential for errors during assembly.

Best,
Kai

discreet rules.

Post Polo AEF.

"Why all the effort?"
Because version 2.2, despite all the time invested so far, still doesn't work everywhere.
The IC doesn't require much "accessories". Therefore, it's more likely to need fewer parts rather than more. The difficulty lies in sourcing them: so far, I've only found suppliers with a minimum order quantity of 55 units and a delivery time of 6 weeks (!). The cost is only 1.50 EUR.
Christian