# SDR ASAA2021032334418

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: March 23, 2021
- Submitted: March 29, 2021
- Operation: Air carrier
- Aircraft: [N494AS](https://openairdocs.org/aircraft/N494AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 41729
- Aircraft time: 18,874 hours, 5,906 cycles
- System (JASC): [2210 · Autopilot System](https://openairdocs.org/jasc/2210)
- Part: Display
- Condition: Defective
- Location: Control Panel
- Part time: 18,920 hours, 5,919 cycles
- Stage of operation: NR
- How discovered: 9
- Nature of condition: O
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2021032334418

## Discrepancy

MCP IAS/MACH BOX HAS WHITE DOT ON AT ALL TIMES. GROUNDED - YES. REMOVED AND REPLACED DFCS MODE CONTROL PANEL IAW B737-900 AMM 22-11-34/401. JTHACH 31086 03/27/2021 ACCOMPLISHED DFCS LRU REPLACEMENT TEST FOR MCP REF AMM 22-11-34/501. ALL TESTS PASSED. ACCOMPLISHED LAND VERIFY TEST REF AMM 22-11-00/201. ALL TESTS PASSED. ALL GROUND VERIFICATION GOOD - ALL PLACARDS REMOVED.

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