# SDR CALA2026073118134

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: July 29, 2026
- Submitted: July 31, 2026
- Operation: Air carrier
- Aircraft: [N34222](https://openairdocs.org/aircraft/N34222), registered now
- Make and model: Boeing 737824
- Aircraft serial: 28931
- Aircraft time: 83,253 hours, 31,155 cycles
- Engine: Cfmint CFM567B262
- System (JASC): [3445 · Air Collision Avoidance System](https://openairdocs.org/jasc/3445)
- Part: Computer
- Part number: 8222911002
- Part serial: 9029
- Condition: Faulty
- Location: Tcas
- Part time: 29,123 hours, 10,864 cycles
- Stage of operation: CL
- How discovered: O
- Nature of condition: J
- Precautionary procedure: A, D
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/CALA2026073118134

## Discrepancy

TCAS FAIL FLAG ON NAVIGATION DISPLAY SHOWS WITH ATC TRANSPONDER SELECTOR AT TA AND SHOWS WITH SELECTOR AT TA/RA FAULT NOT PRESENT, FOLLOWING FIM 34-45 TASK 821, TCAS OPERATIONAL CHECK PASSES AND TCAS BITE PASSES. FURTHER TROUBLESHOOTING REQUIRED. PERFORMED PSEU BITE IAW FIM 34-45 TASK 821, CHECK GOOD. AWAITING EQUIPMENT TO CHECK ATC ANTENNAS IAW D 2 OF FIM 34-45 TASK 821 AFTER SPEAKING WITH TOMC AGAIN IT WAS DECIDED TO REMOVE AND REPLACE THE TCAS COMPUTER. COMPUTER REPLACED REF: AMM TASK 34-45-01 AND OPS TEST WAS GOOD.

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