# SDR ASAA201908029244

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: July 29, 2019
- Submitted: August 3, 2019
- Operation: Air carrier
- Aircraft: [N487AS](https://openairdocs.org/aircraft/N487AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 44108
- Aircraft time: 15,082 hours, 4,814 cycles
- System (JASC): [2210 · Autopilot System](https://openairdocs.org/jasc/2210)
- Part: Control Panel
- Part number: 4082260939
- Part serial: 99081852
- Condition: Failed
- Location: Flight Deck
- Part time: 62,476 hours, 28,843 cycles
- Stage of operation: CR
- How discovered: O
- Nature of condition: J
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA201908029244

## Discrepancy

IN CRUISE AT FL350 AUTOPILOT B RANDOMLY DISENGAGED. GROUNDED - YES. REMOVED AND REPLACED MCP PER B737-900 AMM 22-11-34. OPEN AND TAGGED 4 CIRCUIT BREAKERS. CLOSED AND REMOVED TAGS FROM 4 CIRCUIT BREAKERS. LAND VERIFY TEST PASSED PER 22-11-00. MCP INSTALLATION TEST PASSED PER AMM 22-11-34. DFCS LRU REPLACEMENT TEST PASSED PER 22-11-34.

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