# SDR ASAA2021050134723

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: May 1, 2021
- Submitted: May 3, 2021
- Operation: Air carrier
- Aircraft: [N419AS](https://openairdocs.org/aircraft/N419AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 41734
- Aircraft time: 30,128 hours, 9,714 cycles
- System (JASC): [3460 · Flight Management Computing Hardware System](https://openairdocs.org/jasc/3460)
- Part: Fmc
- Condition: Malfunctioned
- Location: Right
- Stage of operation: NR
- How discovered: V
- Nature of condition: O
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2021050134723

## Discrepancy

RIGHT FMC CDU DISPLAY COMPLETELY BLANKED TWICE FOR ABOUT 10 SECONDS EACH TIME AND THEN RETURNED TO NORMAL. FMC CDU FAILS FLAGS- "CALL FAIL", "MSG OFFSET" LIGHTS ILLUMINATED WHEN DISPLAY BLANKED. GROUNDED - YES. FOUND CDU DISPLAY WORKING. VERIFIED 115 VAC BETWEEN PINS 30 AND 31 OF D2221. CHECKS GOOD. REINSTALLED CDU. OPS CHECKS GOOD REF B737-900 FIM 34-61 TASK 804. 2 C/B'S PULLED AND RESET.

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