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Diagnosis of control unit without a vehicle

 
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dieselcruiser
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Post16-03-2006, 12:15    Subject: Diagnosis of control unit without a vehicle Quote

Hello,

I would like to read the error memory of a control unit with the part number 028 906 021 without having to install it in the car. I have the control unit, an OBD socket with four wires attached, a connector that fits into the control unit, and a laptop with an adapter and VAG-COM software.
Which cables need to be connected where for it to work?


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voss
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Post16-03-2006, 12:47    Subject: Diagnosis of control unit without a vehicle Quote

@dieselcruiser

I cannot help you further.
"But have you considered that as soon as you power on the device and no sensors are connected, it will display/store a large number of errors?"
Or do you want to build a real simulation with all the sensors and actuators, etc.?


Regards,
voss


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dieselschrauber
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Post16-03-2006, 13:55    Subject: Diagnosis of control unit without a vehicle Quote

Hello Dieselcruiser,

If the device is not installed in the car, then a whole host of other errors will immediately appear. I cannot say whether these will overwrite any previously stored, lower-priority errors in your device. But it could happen, and then it would all be for nothing.

So, the best approach would be to place it inside a suitable car. That would likely involve much less effort than simulating a car on a table. What are you up to?

Best regards, Rainer.


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dieselcruiser
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Post16-03-2006, 14:28    Subject: Diagnosis of control unit without a vehicle Quote

I'm currently in the process of transplanting a 1Z engine into a T4. I have a ...021C control unit without WFS (Waste Heat System) and wanted to read it out beforehand. It doesn't fit in my Passat 35i because of the WFS. Since I only have the engine wiring harness for the engine being installed, I'm not entirely sure where to connect the diagnostic socket. This diagnostic socket also comes from another vehicle and has cut-off cable ends. Unfortunately, the donor vehicle, along with the additional wiring harnesses, is no longer available.
A wiring diagram showing how the 4 wires of the diagnostic connector should be connected would be helpful.
I hadn't considered that the absence of the electrical components might create new problems, so I'll probably have to be patient with the diagnostics. Or, I could try connecting everything together beforehand, but I'm not sure if that will work.


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dieselmartin
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Post16-03-2006, 15:41    Subject: Diagnosis of control unit without a vehicle Quote

If you connect the 021 C to your 35i 1Z, then (if anything at all), only _one_ error should appear, namely that the WFS "turns off".

He shouldn't find any errors related to other components, because those are all present in the Passat.

Even a few rotations is what we can achieve before the WFS shuts down.

I also did this test with my 021 AF and a 021 HD:
HD in, connected... running, turns off (everything as expected) icon_smile.gif
Then I deleted the WFS and drove about 500 km.
Now it's back in the AF.

m;
Transparency, Teamwork
... there was another T.

I don't know what the f*ck it was.


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Post16-03-2006, 15:53    Subject: Diagnosis of control unit without a vehicle Quote

However, the ...021C cannot be connected to the 35i's connector with the WFS adapter, because there are small protrusions in the way.


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dieselmartin
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Post16-03-2006, 15:57    Subject: Diagnosis of control unit without a vehicle Quote

Oops...

I didn't know, sorry.

But why do you even want to "have it running beforehand"?
This test run won't tell you whether the engine will actually run properly later. The memory will be full of errors (which is already explained above)...

I think only a test run on the engine itself will provide clarity.

BTW: Do you have any pictures of the "1Z to T4" conversion? Perhaps the colleague's bus, with its 2.4 naturally aspirated diesel engine, might break down someday icon_smile.gif.
Transparency, Teamwork
... there was another T.

I don't know what the f*ck it was.


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Post16-03-2006, 16:01    Subject: Diagnosis of control unit without a vehicle Quote

Here, you can get your nose pierced.

http://i16.ebayimg.com/01/i/06/76/ec/1e_1_b.JPG

Here's the MSA15 (as it would fit on the 35i).
http://www.wiwi-webdesign.de/ebay/steuergeraet/01.jpg

m;
Transparency, Teamwork
... there was another T.

I don't know what the f*ck it was.


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dieselcruiser
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Post16-03-2006, 16:09    Subject: Diagnosis of control unit without a vehicle Quote

I just want to eliminate potential errors from the start, and since you can do this kind of electrical tinkering indoors in a warm environment, I was considering the options I mentioned earlier. Idea.
I don't have any pictures of the renovation yet, but I will take some. I'm just waiting for the temperatures to get a little warmer.
Does anyone have a wiring diagram for connecting the OBD port?


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Post16-03-2006, 16:16    Subject: Diagnosis of control unit without a vehicle Quote

Have you already checked this?

http://volkswagen.msk.ru/
Transparency, Teamwork
... there was another T.

I don't know what the f*ck it was.


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dieselcruiser
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Post16-03-2006, 16:19    Subject: Diagnosis of control unit without a vehicle Quote

Yes, but I haven't found anything suitable. Not even in the 'Help Yourself' manuals for the Golf, Passat, or T4 models.
Are there any other links?


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Post17-03-2006, 19:34    Subject: Re: Diagnosing a control unit without a vehicle Quote

Hello!

dieselcruiser wrote:

I would like to read the error memory of a control unit 028 906 021 ** without having to install it in the car.


That's quite counterproductive, because as soon as you turn it on, you're bombarded with error messages.

Anything that is not present will then be interpreted as an error: control panel, fuel injector adjuster, EGR valve, turbocharger valve, knock sensor, kW sensor, boost pressure, intake air temperature, water temperature, and possibly the engine control unit network.

BYE
TDI mechanics.


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dieselcruiser
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Post21-03-2006, 15:57    Subject: Diagnosis of control unit without a vehicle Quote

Can anyone tell me what the wiring configuration is for the four wires of the diagnostic connector?


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dieselschrauber
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Post21-03-2006, 18:24    Subject: Diagnosis of control unit without a vehicle Quote

"So, now, did you think you needed the pinout diagram for the control unit?"

Should be:
- +12V Pin 45
- GND Pin 24
- K-Line Pin 61

Pin configuration when looking at the connector on the control unit:
Pin 46 ... Pin 68.
LD connector, pin 24... Pin 45.
Pin 1 ... Pin 23.

OBD2 socket:
- +12V Pin 16
- GND Pin 4/5
- K-Line Pin 7
On the shop's homepage, there is a picture.
http://shop.dieselschrauber.de/

The blue connectors are for CAN.

Best regards, Rainer.


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