# SDR ASAA2023040842767

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: April 8, 2023
- Submitted: April 10, 2023
- Operation: Air carrier
- Aircraft: [N934AK](https://openairdocs.org/aircraft/N934AK), registered now
- Make and model: Boeing 737-9
- Registry model: [Boeing 737-9](https://openairdocs.org/model/boeing-737-9) (OpenAirDocs)
- Aircraft serial: 43374
- Aircraft time: 4,027 hours, 1,162 cycles
- System (JASC): [3010 · Airfoil Anti/De-ice System](https://openairdocs.org/jasc/3010)
- Part: Unknown
- Part number: UNKNOWN
- Condition: Unknown
- Location: Unknown
- Stage of operation: DE
- How discovered: V
- Nature of condition: J
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2023040842767

## Discrepancy

AT TOP OF DESCENT (AROUND FL300) WING ANTI-ICE SWITCH WAS SELECTED ON. LEFT VALVE LIGHT ILLUMINATED. TRIED AGAIN AT 10,000 FT AND LEFT VALVE LIGHT ILLUMINATED AGAIN. REFFERED TO QRH. ALTERNATE DEACTIVATION PROCEDURE CW PER CHAP 5-07-01 TABLE 3 ITEM 3. GROUNDED - YES. PERFORMED LEFT WING THERMAL ANTI ICE VALVE HEALTH CHECK PER B737-9 AMM 30-11-11-200-801. 2 CB'S OPENED AND CLOSED. OPS CHECKS NORMAL.

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