# SDR ASAA2020120733654

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: December 7, 2020
- Submitted: December 9, 2020
- Operation: Air carrier
- Aircraft: [N403AS](https://openairdocs.org/aircraft/N403AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 41730
- Aircraft time: 30,610 hours, 9,894 cycles
- System (JASC): [2822 · Fuel Boost Pump](https://openairdocs.org/jasc/2822)
- Part: Pressure Switch
- Part number: 21C1321
- Condition: Inoperative
- Location: Lt Boost Pump
- Stage of operation: IN
- How discovered: V
- Nature of condition: O
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2020120733654

## Discrepancy

NR 1 AFT BOOST PUMP LOW PRESSURE LIGHT REMAIN OFF AT ALL TIMES.  GROUNDED-YES.  REPLACED NR 1 TANK AFT PRESSURE SWITCH (S150), PER B737-900 AMM 28-42-11/401.  OPERATIONS GOOD, PER AMM TASK 28-42-11-700-801.

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