Passat B6 Sedan: Locating & Accessing Handbrake Control Unit for Volkswagen

Center console for disassembly. The rudder is on the middle tunnel.

What are the symptoms that you need to check the driver?
I understand that the button has already been replaced? and checked that the servo housings at the terminals are not broken?

The cracked housing caused the joint to become unsealed from the inside and the contacts to corrode,
you probably have a bad contact on this connector with the new motor,
do not touch this driver because it is functional.
I understand that the errors were deleted with the computer after replacing?

And the motor was replaced when the clamp was blocked or someone noticed a crack early on and changed how everything worked? otherwise since when do you have this permanent bug?
Check these contacts again, even if you have done it 10 times before, check the eleventh one and feel if the plug is reaching the end, if there is a latch, if the latch is holding.
Try to treat the connector with a different preparation, with some contact to the contacts, because it is most likely that it does not connect there and this motor is bidirectional, so there is no strictly current wire, because the controller has an H bridge changing polarity, hence this message about the lack of power, it has the right to also appear in the absence of contact because of the above, I wrote.

I do not understand, on what basis it was found that the old engine is damaged, since replacing it with a new one did not give anything? Was it about this crack in the casing and was it only for this reason that it was replaced?

Have you sprayed this connector on the motor as I suggested? in the first entry, I also asked if the brake button was replaced, because the break can also be there, moreover, as it is with the production date earlier, like mid-2006, it is absolutely to be replaced because they were defective

Look at the websites of companies that regenerate these motors, they have described how you can connect a light bulb in this place and drive without one motor for the time of repair and try to connect the light bulb instead of the motor, you will see for yourself whether there is voltage from the controller.

These motors are identical on both sides, try to swap them, left and right, because I can see that you are combining and there is no certainty that the new one has the right parameters.
Anyway, what is surprising as a new one costs PLN 800, and the regeneration itself costs PLN 300, but only if you send back the old one.

Have you done the reset on the battery? often the rudder hangs and a reset with the clamp is enough. Sometimes it only helps to unfasten and fasten the plug at the controller.

This plug is demountable, see what condition the connectors are in before they are cut, maybe just mechanical cleaning and bending is enough?

It takes 20 minutes to collapse the tunnel. The whole day was spent on forum reflection. Drop this tunnel.

A colleague gives very modest information, I had to look at his posts where he repaired the air conditioning to conclude that it is a 3C2 model with a 2.0PD engine and the 3C0 998 281B motor is sitting there, and there, apart from the motor and staggering gear, there is nothing inside, no sensor, anyway they go only two wires there.
The control is not a relay, but an H bridge with current measurement, as I already mentioned.
A fault in the module, if only on this current shunt, if there was a short circuit on the motor for a long time, this shunt could change the resistance value or simply caught a cold solder. But in this case, the button 3C0927225B also needs to be replaced. The button also shows the day and year of its production, the first 3 digits are the last day, i.e. the year, and if it is earlier than 1506, all were defective up to that date and are subject to replacement.

It is not an ordinary microswitch because, first of all, there are two of them, and secondly, you do not connect it when you press it only through such an interesting plastic mechanism, and usually only one works or alternately, and you don't know what's going on.

Which does not change the fact that the button is definitely not to blame

Well, this is not a button but a switch due to this internal mechanism.
If you have not dismantled the tunnel yet, the last idea is: pull out this switch, turn on the ignition, let it save the errors, then put it back and follow the procedure as after replacing the button. We all keep our fingers crossed for a positive solution to the problem.