The P0814 code in your 2021 Audi S4 indicates a malfunction in the transmission range display circuit. This circuit communicates gear selection information to the instrument cluster and other display systems.
Understanding Range Display Circuit
The S4's transmission sends gear position data to the instrument cluster to display the current gear (P, R, N, D, S) and selected position. P0814 indicates this communication circuit has a problem, affecting what the driver sees.
Common Causes of P0814
- Instrument cluster communication error
- CAN bus wiring issues
- TCM display output failure
- Shift lever position sensor malfunction
- Ground or power supply issues
- Instrument cluster fault
Symptoms of Display Circuit Malfunction
- Incorrect or missing gear display
- Gear indicator flashing or erratic
- Check engine light on
- Multiple display system warnings
- Shift position indicator blank
- Possible shift interlock issues
Audi Virtual Cockpit Considerations
The S4's digital instrument cluster receives gear position data through the vehicle's CAN network. P0814 may affect the Virtual Cockpit display even if the actual transmission functions normally.