Help with Gearbox Malfunction - DTC: Shift Fork 4 Position Sensor / P2848 00 [096]

[Arese]

Hey everyone,

Last week as I was driving my B8.5 S5 I got a Gearbox malfunction message on the dashboard, it said reverse is not working and a TPMS (tire pressure Monitoring System) light lit up as well. When the lights came up I lost traction for a couple of seconds as the engine would be revving up but no power was transmitted to the wheels. Eventually, the car managed to shift to a gear and I was able to move forward. I stopped immediately, I couldn't reverse the car so I turned off the car. After 5 min I turned it on and all the lights were gone, reverse gear worked and I was able to drive without issue. I thought it was just a glitch.

Today the exact same issue appeared. As I was accelerating I got a gearbox malfunction message, reverse unavailable and TPMS light on the dashboard. The car struggled to shift and skipped gears from D4 to D7, still I managed to pull over and turn off the engine.


I got home and scanned the car with VCDS and I got the below codes.

18056 - Shift Fork 4 Position Sensor
P2848 00 [096] - Incorrect Neutral Position
Intermittent - Not Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 2
Reset counter: 40
Mileage: 35073 km
Date: 2021.09.10
Time: 15:35:10
Engine RPM: 2878 /min
Transmission input speed: 2878 /min
Transmission output speed: 528 /min
Engine torque: 20 Nm
ATF temperature: 100 °C
Accelerator pedal position: 4.8 %
Clutch status: Kupplung 1 kann Moment übertragen
Unlearning counter according OBD: 40

01315 - Transmission Control Module
013 - Check DTC Memory - Intermittent
Freeze Frame:
Fault Status: 00101101
Fault Priority: 6
Fault Frequency: 2
Reset counter: 29
Mileage: 35073 km
Time Indication: 0
Date: 2021.09.10
Time: 15:35:11

Online I found the below possible causes for code P2848.

Outdated Transmission Control Module (TCM) program (Reprogram TCM)
Faulty Transmission Control Module (TCM)
Faulty Transmission Assembly

Can someone help me understand what's a TCM? Is it a known issue on B8.5 S5? Is it known to fail on those cars? Where is it located? Can I visually inspect it?
Will I have to take it to Audi to fix it?

Thanks in advance for any insights you may have. I never dealt with transmission however, I'm pretty hands-on so please let me know if there is anything I can do/check myself before taking it to Audi.

Thanks

[Arese]

Here's a pic of my dashboard when the issue occurred