# SDR ASAA2019071930098

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: July 19, 2019
- Submitted: July 19, 2019
- Operation: Air carrier
- Aircraft: [N407AS](https://openairdocs.org/aircraft/N407AS), registered now
- Make and model: Boeing 737-900ER
- Registry model: [Boeing 737-900ER](https://openairdocs.org/model/boeing-737-900er) (OpenAirDocs)
- Aircraft serial: 41731
- Aircraft time: 26,458 hours, 8,478 cycles
- System (JASC): [4970 · APU Indicating System](https://openairdocs.org/jasc/4970)
- Part: Module
- Part number: 38762871
- Part serial: AGE17778
- Condition: Defective
- Location: Apu
- Part time: 2,801 hours, 5,293 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/ASAA2019071930098

## Discrepancy

RECENT INSTALLED APU DMM IS PROVIDING ERRONEOUS DATA. GROUNDED - YES. REPLACED DMM AND PERFORMED GOOD INSTALLATION TEST PER AMM 49-72-11.

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