# SDR CALA2026042715736

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: April 23, 2026
- Submitted: April 27, 2026
- Operation: Air carrier
- Aircraft: [N37518](https://openairdocs.org/aircraft/N37518), registered now
- Make and model: Boeing 737-9
- Registry model: [Boeing 737-9](https://openairdocs.org/model/boeing-737-9) (OpenAirDocs)
- Aircraft serial: 64495
- Aircraft time: 17,860 hours, 5,899 cycles
- System (JASC): [2750 · Trailing Edge Flap Control System](https://openairdocs.org/jasc/2750)
- Part: Fseu
- Part number: 285A12005
- Part serial: F08188
- Condition: Failed
- Location: Zone 100
- Part time: 17,823 hours, 5,889 cycles
- Stage of operation: CL
- How discovered: O
- Nature of condition: F
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/CALA2026042715736

## Discrepancy

FLAPS STUCK AT 5 AFTERT/ T/O .ALT FLAPS DID NOT WORK UPON ACFT ARRIVAL FOUND FAULT CODE LATCH 27-51351 AND OVERHEAD MAINTENANCE LIGHT ON . T/S REF FIM 27-51 TASK 802 . MSG CLEARED AND LIGHT EXTINGUISHED . ADD FAULT: 27-51351 PER TOMC REQUEST REMOVED AND REPLACED FSEU REF AMM 27-51-01/401, UP TO AND INCLUDING 3.G.(3).  DURING TRAILING EDGE FLAP LOAD RELIEF SYS BITE TEST AT STEP 3.G.(4), TEST FAILED REF AMM 27-51-00-740-803, STEP 8.F.(2)(R).  FLAP LEVER FAULT AT UNIT 10,   FURTHER T/S REQD. PERFORMED FIM 27-51 TASK 809 ON OLD FSEU. FOUND FLAP LEVER POS SENSOR OUT OF LIMITS (55.9 AT FLAPS 10, LIMIT 52.3-52.9). ADJUSTED SENSOR IN REFERENCE TO AMM 27-51-06-820-801. PERFORMED FLAP LOAD RELIEF SYSTEM BITE, TEST PASSED. REINSTALLED NEW FSEU, BITE TEST FAILS AND FLAP LEVER POS SENSOR SHOWS 0.0 IN ALL POSITIONS. SUSPECT BAD FROM STOCK FSEU. WITH TECH SUPPORT HELP, FOUND THAT NEW FSEU WAS NOT SEATING FULLY. APPLIED MANUAL PRESSURE TO SEAT FSEU INTO RACK FULLY. ALL TESTS NOW CHECK GOOD.

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