TAS2-A222
TAS2_a222_compressorPrefillFault
Also written as TAS2_A222 / TAS2 A222 / TAS2_a222_compressorPrefillFault / tas2_a222_compressorprefillfault
Why does the exact Tesla alert ID matter?
Record the exact alert ID, including underscores, suffixes, and companion alerts. Tesla alerts that look similar can point to different modules, timestamps, and service procedures.
What does TAS2-A222 mean?
Tesla alert code in the Thermal Architecture System v2 (TAS2) module. The alert checks for compressor prefill faults every 100ms. Set: Compressor prefill will timeout during a prefill operation if the pressure derivative remains under 1 bar/second for 10 seconds. Clear: Single drive-rail cycle Note: A prefill operation is performed before opening the valves to an air spring or the reservoir. Prefill works by activating the compressor with the spring and reservoir valves closed, so that the gallery pressure increases. This reduces the change in pressure upon opening of the valves, similar to the precharge sequence for the high-voltage battery or on-board chargers. Prefill will fail if: a valve is open or leaking (pressure escapes from the gallery) the compressor does not run compressed air escapes before the valve block
Original Description
The alert checks for compressor prefill faults every 100ms. Set: Compressor prefill will timeout during a prefill operation if the pressure derivative remains under 1 bar/second for 10 seconds. Clear: Single drive-rail cycle Note: A prefill operation is performed before opening the valves to an air spring or the reservoir. Prefill works by activating the compressor with the spring and reservoir valves closed, so that the gallery pressure increases. This reduces the change in pressure upon opening of the valves, similar to the precharge sequence for the high-voltage battery or on-board chargers. Prefill will fail if: a valve is open or leaking (pressure escapes from the gallery) the compressor does not run compressed air escapes before the valve block
Affected Tesla Models
What You May Notice
- Thermal Architecture System v2 alert: The alert checks for compressor prefill faults every 100ms. Set: Compressor prefill will timeout during a prefill operat
- Reduced charging speed in cold weather or battery pre-conditioning required
- HVAC performance may be slightly affected
How to Diagnose and Resolve
- 1 Reboot the vehicle
- 2 Check coolant levels if accessible (Model S/X only)
- 3 Avoid DC fast charging until battery temperature normalizes
- 4 Schedule service if the alert appears in warm ambient conditions
Severity Notes
TAS2-A222 is an Alert in the Thermal Architecture System v2 system. Confirm the vehicle screen and Tesla app show no driving or charging restrictions, and schedule service if the alert returns.