Engine Control Unit (ECU): Where to Buy?

"After I managed to obtain the original data for my Any 1.2 model from 1999 and had a 'professional' solder it in, my engine control unit (ECU) is completely broken. It seems like my car no longer recognizes the ECU, because the car behaves the same way with or without the ECU installed, and the glow plug light is also no longer working."

Okay, so my question is, does anyone know where I can find a used starter generator? Also, what should I be aware of regarding the immobilizer or other things? And is it easy to just replace it with another one, or do I have to go to VW and buy a new one?

I would appreciate a prompt response.

P.S. Would it be worth considering/is it possible to obtain a license from a different model?

The part doesn't necessarily have to be broken. It could also be a soldering error, or something might have gone wrong while programming the EEPROM.

Best regards,
Matthias.

I suspect a 98% chance of a soldering error, as I'm 100% certain that the EEPROMs I've tried (using socket adapters) are working correctly. Could the soldering process have damaged the control unit due to a short circuit or something else?

No, not usually. You need to open the ECU again, clean everything with contact cleaner, resolder the PROM, and then it should work.

Best regards,
Matthias.

"@Troubleshooter: But that assumes you're proficient in soldering. I wouldn't use contact spray inside an electronic control unit. Because it's aggressive and conductive, it can easily cause problems. It might be useful for a heavily corroded connector to remove corrosion and re-establish contact. But with SMD components and their correspondingly small pitch and track widths... I'm not sure."

If you cook something for too long and at the wrong temperature, traces on the circuit board can sometimes detach .
It seems they saved money in the wrong place during the decommissioning process. It's better to have ONE point of contact to whom you hand over the system and to whom you can also hold accountable if they fail to properly decommission it.
I would have Löterich pay for it.

Best regards, Rainer.

@Rainer
That's exactly the stuff I was talking about. We use it to clean every ECU. Also, this stuff is NON-conductive.

Besides, I don't think it's particularly bad that the car won't start.
It's something that has happened to everyone who deals with this subject matter at least once.

There aren't that many possible causes.
File does not fit.
The EEPROM was not programmed correctly.
Soldering defects.
The base is junk.
ECU is junk.

All of this could be quickly and affordably clarified by contacting a tuner near you.

Best regards,
Matthias.

Hi Matthias,

I would probably call that product "degreaser" rather than "contact cleaner," even though the manufacturer labels it as "contact cleaner."
You could try going to AhDeUh sometime, and then you can say, "Please, one can of contact cleaner."
Next, you spray it nicely into your STG, and then you'll understand what I mean .
But as a tip for **** soldering professionals, using a generous amount of soldering flux will make the ECU run smoothly .

Best regards, Rainer.