# SDR CALA2026052016421

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: May 17, 2026
- Submitted: May 20, 2026
- Operation: Air carrier
- Aircraft: [N19986](https://openairdocs.org/aircraft/N19986), registered now
- Make and model: Boeing 787-9
- Registry model: [Boeing 787-9](https://openairdocs.org/model/boeing-787-9) (OpenAirDocs)
- Aircraft serial: 66145
- Aircraft time: 25,629 hours, 2,476 cycles
- System (JASC): [2160 · Cabin Temperature Control System](https://openairdocs.org/jasc/2160)
- Part: Pcu
- Part number: 7110140H01
- Part serial: 765
- Condition: Faulted
- Location: Left
- Part time: 34,378 hours, 3,791 cycles
- Stage of operation: CL
- How discovered: O
- Nature of condition: J
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/CALA2026052016421

## Discrepancy

CABIN TEMP CONTROL, ONE OF THE LT PCU CHANNELS HAS FAILED.   DB 42 GPM_GENERAL OPS (RIGHT 4) DB 42 GPM_GENERAL OPS (LEFT 1) REF L/P 8930547 FOR CORRECTIVE ACTION CABIN TEMP CONTROL L STATUS MESSAGE PERFORMED FIM TASK DMC-B787-A-21-60-F1-65A-421A-A FOR CABIN TEMP CONTROL L STAUS MESSAGE WITH GROUND TEST FAILING FOR MM 45-16521. PERFORMED FIM TASK DMC-B787-A-45-10-F1-23A-421A-A WITH ALL GROUND TESTS PASSING BUT STATUS MESSAGE STILL UNABLE TO REMOVED AND REPLACED PCU LT IAW DMC-B787-A-21-51-20-00D-720A-A AND DMC-B787-21-51-20-00D-520A-A WITH STATUS MESSAGE CLEARING.   COMPLETED DMC TASK DMC-B787-A-21-51-20-00D-720A-A FROM STEP C.11 TO COMPLETION. OPS CHECK PASSED NO MSG NOTED.

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