TDI "Wiring Issues": Golf 3 Engine Control Problem?

Hi.

Here's the translation:

"My sister's Volkswagen Golf 1Z, a 90 hp TDI from 1994, had some problems last week. The car wouldn't start (it cranked for about 5 seconds, usually it starts right away), and then she saw smoke coming from the front. She turned off the ignition, opened the hood (she knows how!), and the smoke disappeared. There was nothing visible. Another attempt to start the engine, but it just cranked and wouldn't fire up."

The independent garage has now picked up the car and has replaced the engine wiring harness, as it seems there were some damaged sections. However, the car still won't start.
Their suggestion: The control unit might be damaged. It's best to try a different one for testing. (They are really fair; they try to find a cost-effective solution for the customer and don't just start replacing parts randomly.)

Now the questions: Is there a standard problem in this area?
Does the control unit from that production year have a WFS (Wireless Flight System) integrated?
The part number appears to be 028 906 021 C (which the workshop wrote down for my sister).

I can't find the device either through Uncle Edgar or the Bosch eCAT system. Could the part number be correct?

Does anyone happen to have a suitable control unit available for loan or sale?
Does anyone know of alternative engine control units (ECUs), or their part numbers, from other vehicles in the 1Z series?

What else can I check when I get to the vehicle? I'd like to be fully equipped with information and parts when I drive by, as it's unfortunately about 250 km each way. And you have to ride your bike every day now, not just 2 km .

Sure, no problem. Here's the translation:

"Thank you in advance."

Best regards, Matze.

Quote:

What else can I check when I arrive at the vehicle?

First, check all the fuses. It would also be interesting to know exactly which wires are carbonized and why, in order to draw conclusions about potential consequential damage.
A possible cause could also be a broken cable within the wiring harness between the starter and the car body, specifically in the area where the cable bundle runs towards the battery. If, for example, terminal 50 comes into contact with a signal wire, it can become quite uncomfortable. I would definitely inspect and check this area.

Hi.

How about the WFS? Does the control unit (if the number is correct?) have a WFS? If so, is it WFS 1? (Just guessing based on the year of manufacture). Then I would need the 4-digit login code (which my sister probably doesn't have...).

Are there any alternative control units that are compatible and do not have a WFS (Wireless Function System)? If so, what is the part number?
Would you like one of those?

If we can believe the search results, one engine control unit with the number 028 906 021 C has a WFS (Wastegate Flap Sensor), while the other does not . What is correct here? And what would be alternatives without it? If the search results are accurate again, the atmospheric pressure sensor is located outside the engine control unit, while the boost pressure sensor is integrated.

Best regards, Matze.