A3 8P Dashboard Gauges/Lights Failure Fix

Hello,
I have an Audi A3 8P, manufactured in late 2003, with engine code BGU and a 1.6-liter engine.

This has happened to me for the second time now.
I get into my car early and try to start it. The instrument panel remains dark (no warning lights), the needles stay at zero, and the engine immediately shuts off again.

The first time it happened, I had the car towed, and after about 1 kilometer, the instrument cluster suddenly turned back on, and everything was okay.

Now I've connected the PC, and by clicking on "Gateway Vehicle List" in VCDS, the instrument cluster suddenly turned on again .
Can you help me? I've already read about cold solder joints or a faulty IC on the AI board that's responsible for the 5V power supply.
Schaltpläne? Erfahrung? Pictures?
Sure, no problem!


Sure, here's the translation:

"Here are the mistakes:"
Motor electronics:

2 error codes found:
18062 - Please read the error memory of the instrument cluster.
P1654 - 009 - Short to ground / Open circuit - Intermittent.
Environmental conditions:
Speed: 1376 RPM
Temperature: 75.0°C
Last: 3.9%
Speed: 44.0 km/h
Speed: 0 RPM.
Temperature: 21.0°C
Last: 8.6%
Speed: 0.0 km/h
17978 - Engine control unit locked.
P1570 - 008 - Implausible signal.
Environmental conditions:
Speed: 0 RPM.
Temperature: 21.0°C
Voltage: 10.81 V
Binary value: 00000001
Speed: 0 RPM.
Temperature: 21.0°C
Voltage: 12.34 V
Binary value: 00000001
Readiness: 0000 0000


Comfort system:
"One error found:"
00955 - Key 1
005 - No or incorrect initial setup/adaptation - Sporadically.
005 - No or incorrect initial setup/adaptation - Sporadically.

I checked and cleaned the grounding points in the driver's and passenger footwells (nothing unusual was visible). I also checked the two grounding points in the battery tray, and they were fine. I'm not sure where else there might be any important grounding points...

Today, while driving, the instrument cluster suddenly went out, including the air conditioning. The car continued to run...
Then I stopped, turned off the engine, and encountered the same problem: the immobilizer was blocking the car.

Error:

Engine control unit locked - intermittent.
"Dashboard fuse error - attempted to read the combination instrument (but no error code appeared on the instrument cluster)."

Short circuit / interruption at terminal 50 - intermittent.



After the engine failed to start four times, the display came back on, the lights turned on again, and I was able to start the car.

I took my car to a workshop, and they said the ignition switch seems to be starting a bit late... I could replace it. But I'm not sure if that's related to my main problem...

Can you give me some advice? Have you ever troubleshooted this problem yourselves?
I would really appreciate it. I'm going to expand the AI and then adjust the settings... Maybe I'll see something.

See you later.
WoS.