Passat GTE 2016 only starts when it feels like it

Here's a spin-off of my other topic, for better organization. Sure, I can move it if necessary.

So, I've essentially disabled my Passat due to what appears to be an improperly performed battery replacement. Now, with a new body control module, it starts and runs perfectly... when it actually starts. He usually doesn't do it.

You can spend hours trying without it going into "ready" mode for electric driving or starting the internal combustion engine. Half a day later, it might start on the second or third attempt. Try it, then don't do it for 2 days, and then don't do it for 50 attempts.

No patterns detected. No relevant errors. Please find an automatic scan attached. The transmission pressure error displayed in the scan disappears once the vehicle is in motion. According to VW, the communication error in the high-voltage inverter is normal if a new/larger high-voltage battery has been installed.

Okay, so nothing related to starting or being ready to drive.

The only anomaly I've found is that the steering column module is not granting permission (see image). I also retrieved the following states from the WFS in parallel.

Terminal_15_Kessy_specified_value: one.
Terminal_15_Kessy_actual_value: one.
Terminal_15_central electric_actual_value: one.
Terminal_15red_Kessy_specified_value: one.
Terminal_15red_Kessy_actual_value: one
Terminal_S_Kessy_specified_value: one.
Terminal_S_Kessy_actual_value: one
Terminal_S_central electric_actual_value: one
Terminal_50_Kessy_specified_value: one.
Terminal_50_Kessy_actual_value: one
ZAT_pressed: a
Shift lever position: Park - engaged and locked.
Request active: Condition not met.
Steering column lock release: Condition not met.
Immobilizer release: Condition met.
No active error mode: Condition met.
Key signature validity: Condition met.
Control Module Voltage: 13.109 V
Driver information: Key position replication function in the workshop: not active.
Driver information: Roll-over warning system, not active.
Driver information: Emergency shutdown - not active.
Internal_key_position: no_message
Driver information: Comfort deactivation not active.
Vehicle speed: 0.0 km/h
Motor speed: 0.0 rpm.


The download of the key information from the WFS to the steering column is also successful every time, but I have only observed this, without logging it.

"What could be the reason that all conditions for releasing the driving readiness are met, the requirement is active, but the steering column module is not releasing?"

After someone patiently convinced me that the transmission control unit could also be faulty, I have now installed a new one.

And lo, the car starts again, and also goes back to "Ready" electrically with each attempt.

You can't actually drive it yet, because you can't put it in gear... but that was to be expected, and there's now a new thread about it.