# SDR CALA2021040500420

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: April 5, 2021
- Submitted: April 5, 2021
- Operation: Air carrier
- Aircraft: [N673UA](https://openairdocs.org/aircraft/N673UA), registered now
- Make and model: Boeing 767322
- Aircraft serial: 29241
- Aircraft time: 75,020 hours, 15,814 cycles
- System (JASC): [3412 · Outside Air Temperature Indicator/Sensor](https://openairdocs.org/jasc/3412)
- Part: Tat Probe
- Condition: Faulted
- Stage of operation: CL
- 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/CALA2021040500420

## Discrepancy

TAT PROBE MESSAGE ON LIFTOFF FOUND CB P63 GRID L 18 "L TAT" PROBE HEAT OPEN. CLOSED CB AND PERFORMED OPS CK REF AMM 34-12-02-404-008. CB REMAINED CLOSED THROUGH OUT TEST. AS PRECAUTION REPLACED K411 LEFT TAT PROBE CURRENT SENSING RELAY IN P33 PANEL. ALSO PERFORMED TAT OPERATION TEST IAW AMM 30-33-00. TAT OPERATIONAL TEST GOOD.

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