A4 B5 1997: Faulty WFS - Troubleshooting Guide

Hello!
After unsuccessfully troubleshooting the issue, I hope for your expert assistance.
For the past 3 years, the engine has been turning off 1-2 times for about a second after starting. Sometimes, it starts and runs normally right away.
Starting in 2006, around a week before Christmas, the WFS will go on strike completely.
When I turn the ignition on, the fuel pump runs briefly. Instead of turning off, the check engine light flashes. I avoid trying to start it so as not to drain the battery. After about 100 attempts, it sometimes works and the car starts and stays running.
In October, I had my car inspected at a friend's workshop; he runs an independent garage.
He also read and cleared the error codes.
The analysis:
Engine control unit locked... 35-10 Interrupt.
01176 Key.............07-10 Signal too low - interruption.
Actions:
Replaced the electrical switch on the ignition lock (it had broken off).
We've also already tried a new reading head.
The same error is still present.
Does the WFS (Wireless File System) already come integrated in this model?
Please help me! Does anyone perhaps have a wiring diagram?
Best regards,
TOM.

Have you tried using the spare key by itself yet? It's also possible that the metallic clinking of the keychain is interfering with the signal.

Yes!
I've already tried using the spare key and the workshop key by themselves.

In the 1997/98 model year, the windshield wiper system (WFS) was moved to the instrument cluster (IC). If your car has a clock with minute markings, it still has the external WFS. Otherwise, it already has the WFS II, which is located in the IC.

As I see it, the pickup coil is receiving the signal, but it's too weak. It's possible that the cable connected to the pickup coil has a bad connection or a worn spot somewhere.

Trace the cable to the AI (Artificial Intelligence module) or the WFS (Window Film System) located behind the ashtray, underneath the radio.

It's also possible that the reading head is misaligned or positioned too far away.

The clock has minute markings!
How do I access the WFS if it's located behind the ashtray?
I already have the clips for removing the radio, but there's still the climate control unit underneath.
Can you remove the entire console?
I'm going to the car now to take a closer look; I'll get back to you later.
Best regards,
TOM.

To properly access the WFS (presumably a component or system), you need to remove the entire center console, including the tunnel section.

First, you need to remove the radio. Then, two 8mm hex screws will become visible on the top left and right sides. Once you've removed those, you can pop off the trim panel. To remove the air conditioning unit, you'll need a 7mm Allen key (I think). You can then simply pull it out, and disconnect the four connectors at the back.

Now you should be able to see the WFS. It's a small silver box.

Now the tunnel needs to be removed. It's also fastened with 8mm hex bolts in the driver and passenger footwells. The screws are located under small covers that you can remove with a small screwdriver. Be careful though, as they break easily. Additionally, there are one or two more screws at the back, underneath the cigarette lighter/ash tray. They're considerably larger, I think 17mm.

To expand the center console, you need to remove the handbrake cover and the gear stick surround on the shift knob. You can simply pull the handbrake handle forward after releasing the retaining clip located at the bottom of the handle (in the middle, towards the back where it connects to the cover). The cover can then be easily pulled off. I don't have any information about leather covers, as I only have the standard plastic one.

After that, you need to remove the wiring harness and then you can take off the tunnel.
Just be careful with the OBDII connector; the cables can easily come loose if you don't clip it down beforehand.

The WFS should now be accessible without any problems.

I recommend that you first double-check the position of the reading coil to ensure it's securely in place where it should be, and if possible, move it closer to the key.

I would start by checking and possibly replacing the wiring harness of the windshield wiper system (WFS) that connects to the reading coil, as it often breaks near the steering column due to being tightly routed there.

Part number: 8D0 972 275 - costs 15 euros.

I just received a "How-to" book.
This allowed me to locate the position of the WFS. It is attached to the left console bracket.
Removed the cover from the fuse box, unscrewed the four screws holding the shelf under the steering wheel in place, and pulled the shelf out. You can see a white box, about the size of a cigarette pack, hanging on the left side of the center console.
I tested the cable to the reading head and it shows no breaks in continuity. With the reading head connected, the loop resistance is 22 ohms. The new reading head has the same resistance. Therefore, I assumed the problem lies with the wheel flange system (WFS).
I once resoldered the connector strip on the WFS and checked the electrolytic capacitors, but it didn't work!
I was also unable to find a fuse specifically for the WFS (Wireless File System).
Is the WFS powered by the MSG?
A VAG employee mentioned that there's a sensor on the engine that might also be related to this issue.
Could it be that the MSG is malfunctioning and not communicating with the WFS?
Questions upon questions.
I believe that I now have to bite the bullet and take the car to VAG.
If anyone still has an idea, please reply!
Best regards,
TOM.