# SDR CALA2026042415686

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: April 23, 2026
- Submitted: April 24, 2026
- Operation: Air carrier
- Aircraft: [N17405](https://openairdocs.org/aircraft/N17405), registered now
- Make and model: Boeing 737-9
- Registry model: [Boeing 737-9](https://openairdocs.org/model/boeing-737-9) (OpenAirDocs)
- Aircraft serial: 67647
- Aircraft time: 3,294 hours, 1,084 cycles
- System (JASC): [2781 · Leading Edge Slat Position Indicating System](https://openairdocs.org/jasc/2781)
- Part: Proximity Sensor
- Part number: 8020701
- Condition: Faulted
- Location: Flap Sys
- Stage of operation: AP
- 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/CALA2026042415686

## Discrepancy

LEADING EDGE FLAP  TRANSIT LT W/ FLAPS 30 SELECTED. REPEAT GRIPE . LOCKING FOR POSITIVE REPAIR LATCHED MESSAGE. CHECKED FAULT HISTORY FOR FLIGHT CONTROLS REF AMM TASK 46-13-02-700-806, FOUND MAINTENANCE MESSAGE 27-81219 PER FIM 27-81 TASK 825, S171 LE FLAP 2 EXTEND SENSOR REQUIRES REPLACEMENT. UNLOCKING FOR UPDATE R/R LEFT LEADING EDGE FLAP PROXIMITY SENSOR 2 (S171) IAW AMM REF 27-88-11/401. STILL NEEDS TO BE SECURED AS WELL AS OPS CHECK. LOCKING FOR POSITIVE FIX UNLOCKING FOR POSITIVE FIX CLOSEOUT SECURED LE FLAPS POS SENSOR S171 IAW AMM TASK 27-88-11-400-802. PERFORMED OPS CHECK IAW AMM 27-88-11-700-801. OPS CHECK GOOD. NO LE FLAPS TRANSITT LIGHT. PARTS USED:  29-2788-3-0007,QTY :1 ADD EMP:U409696

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