# SDR ASAA2021112536749

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: November 25, 2021
- Submitted: November 30, 2021
- Operation: Air carrier
- Aircraft: [N492AS](https://openairdocs.org/aircraft/N492AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 44110
- Aircraft time: 22,123 hours, 7,041 cycles
- System (JASC): [7530 · Compressor Bleed Control](https://openairdocs.org/jasc/7530)
- Part: Actuator
- Part number: 1226400
- Part serial: YU125995
- Condition: Faulty
- Location: #1 Engine
- Part time: 22,150 hours, 7,048 cycles
- Stage of operation: IN
- How discovered: O
- Nature of condition: O
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2021112536749

## Discrepancy

REF T/C 78273000, ENG # 1 SHORT TIME FAULT 75-30451, THE VSV POSITION SIGNALS DISAGREE. FAULT SET ON LEG 1,2,4 AND 8. GROUNDED - YES. NO RECENT FAULTS FOUND IN CDU. FAULT HISTORY SHOWED FC 75-30451 ON LEGS 8 AND 9. EEC TEST PASSED, REMOVED AND REPLACED #1 ENG RH VBV VALVE ASSY. REF B737-900 AMM 75-32-02 SYSTEM OPS CK. NO LKS OR FAULTS NOTED.

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