# SDR AALA202608198150

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: August 17, 2026
- Submitted: August 19, 2026
- Operation: Air carrier
- Aircraft: [N874NN](https://openairdocs.org/aircraft/N874NN), registered now
- Make and model: Boeing 737823
- Aircraft serial: 31129
- Aircraft time: 44,360 hours, 19,184 cycles
- System (JASC): [4990 · APU Oil System](https://openairdocs.org/jasc/4990)
- Part: Oil Cooler
- Condition: Inoperative
- Location: Zone 300
- Stage of operation: CR
- 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/AALA202608198150

## Discrepancy

AIRCRAFT WAS GROUNDED: APU WAS RUNNING AND THE LIGHT EXTINGUISHED. AFTER 15 MINUTES APU SHUTDOWN AND THE R IGHT SOURCE OFF LIGHT CAME BACK ON. AFTER QRH PERFORMED DUE TO SOURCE OFF LIGHT, APU WAS RUNNING AND THE LIGHT EXTINGUISHED. AFTER 15 MINUTES APU SHUTDOWN AND THE RIGHT SOURCE OFF LIGHT CAME BACK ON. QRH PERFORMED AND DIVERTED TO THE NEAREST SUITABLE (NAS) FOLLOWING THE CHECKLIST. EMERGENCY DECLARED AND AIRCRAFT LANDED WITHOUT INCIDENT. MAINTENANCE REPLACED APU OIL COOLER IAW AMM 49-91-41.

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