# SDR ASAA2018113097157

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: November 29, 2018
- Submitted: November 30, 2018
- Operation: Air carrier
- Aircraft: [N594AS](https://openairdocs.org/aircraft/N594AS), registered now
- Make and model: Boeing 737890
- Aircraft serial: 35191
- Aircraft time: 40,687 hours, 12,247 cycles
- System (JASC): [4960 · APU Controls](https://openairdocs.org/jasc/4960)
- Part: Control Unit
- Part number: 2118966222
- Part serial: 50F0432
- Condition: Failed
- Location: Apu
- Part time: 63,636 hours, 24,584 cycles
- Stage of operation: IN
- How discovered: 9
- Nature of condition: O
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2018113097157

## Discrepancy

FLT CREW REPORTS NO DUCT PRESSURE FROM APU BLEED. GROUNDED - YES. REMOVED AND REPLACED APU ECU. PERFORMED APU START AND BITE TEST; BOTH GOOD. NO FAULTS. DUCT PRESSURES FROM APU BLEED GOOD. REF  B737-800 AMM 49-61-12.

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