# SDR CALA2026012113127

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: January 18, 2026
- Submitted: January 21, 2026
- Operation: Air carrier
- Aircraft: [N37542](https://openairdocs.org/aircraft/N37542), registered now
- Make and model: Boeing 737-9
- Registry model: [Boeing 737-9](https://openairdocs.org/model/boeing-737-9) (OpenAirDocs)
- Aircraft serial: 64470
- Aircraft time: 11,278 hours, 3,768 cycles
- System (JASC): [3445 · Air Collision Avoidance System](https://openairdocs.org/jasc/3445)
- Part: Computer
- Part number: 9400351001
- Part serial: TPA21659
- Condition: Faulty
- Location: Tcas
- Part time: 11,056 hours, 3,741 cycles
- Stage of operation: CR
- How discovered: O
- Nature of condition: O
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/CALA2026012113127

## Discrepancy

TCAS FAIL FLAG SHOWS ON ND CAPTAIN'S.   PERFORMED WIRING CHECK FOR TCAS TOP & BOTTOM ANTENNA & CHECKED TCAS COMPUTER UNIT IAW FIM 34-45 TASK 803, & WDM 34-45-21-10. WIRING CHKD GOOD, BUT FOUND TCAS COMPUTER UNIT FAILED.  R & R THE TCAS COMPUTER UNIT IAW AMM 34-45-01/401. OPS CHKD GOOD.

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