# SDR CALA2026021613770

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: January 29, 2026
- Submitted: February 16, 2026
- Operation: Air carrier
- Aircraft: [N37556](https://openairdocs.org/aircraft/N37556), registered now
- Make and model: Boeing 737-9
- Registry model: [Boeing 737-9](https://openairdocs.org/model/boeing-737-9) (OpenAirDocs)
- Aircraft serial: 67579
- Aircraft time: 10,207 hours, 3,352 cycles
- System (JASC): [2910 · Hydraulic System, Main](https://openairdocs.org/jasc/2910)
- Part: Hydraulic System
- Condition: Overserviced
- Location: Zone 100
- Stage of operation: IN
- How discovered: O
- Nature of condition: W, B
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/CALA2026021613770

## Discrepancy

PACK LIGHT COMES ON DURING FLT,  LT PACK LIGHT CLB THRU FL200 BURN ODOR FOLLOWED BY PACK LIGHT ON. QRH TRIP R ESET UNSUCCESSFUL. FAULT HISTORY SHOWS MAINTENANCE MESS. 21-55100 (LT PACK OVERHEAT SHUTDOWN IN FLT ) FIM 21-51 TASK 819 ALSO MAINTENANCE MESGE. 21-30301.  LOW AIR SUPPLY OR HIGH FUSELAGE LEAKAGE FIM 21-31 TASK 839 , THIS FAULT OBSERVED BY THE CPC-2 AFTER EXPERIENCING PACK SHUTDOWN . REQUIRES ACCOMP OF FIM TASKS ASSOCIATED WITH FAULTS & FOR BURN ODOR REPORTED BY PILOTS REQUIRES  FIM 21-00 TASK 830 . RAN LT PACK SEVERAL TIMES- OPS WAS NORMAL.  DID NOT TRIP.  LT RAM AIR INLET DOOR ACTUATOR FOUND TO BE OPS INTERMITTENTLY. ACTUATOR REPLACED ON NON ROUTINE 3241839. AS FOR THE BURN ODOR FOUND B SYS HYD TO BE OVER SERVICED. ADJUSTED HYD FLUID LEVEL. RAN PACKS SEVERAL MINS & ODOR DISCIPATED. ALL OPS CHKD NORMAL. IAW AMM 21-00-00-800-803, & 12-12-00-610-801.  LT RAM AIR DOOR ACT R & R . HYD SYS B FLUID LEVEL WAS ADJUSTED FROM OVERFILLED TO PROPER LEVEL. PACKS WERE RAN SEVERAL MINUTES WITHOUT TRIPS. ODOR DIMINISHED WITH EVERY PACK RUN. ALL OPS CHKD NORMAL. IAW AMM 21-00-00-800-803 & 12-12-00-610-801.

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