# SDR ASAA2021062735191

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: June 27, 2021
- Submitted: July 7, 2021
- Operation: Air carrier
- Aircraft: [N533AS](https://openairdocs.org/aircraft/N533AS), registered now
- Make and model: Boeing 737890
- Aircraft serial: 35201
- Aircraft time: 38,914 hours, 11,262 cycles
- System (JASC): [2210 · Autopilot System](https://openairdocs.org/jasc/2210)
- Part: Control Unit
- Part number: 4082260939
- Part serial: 96091013
- Condition: Faulted
- Location: Autopilot Sys
- Part time: 67,091 hours, 27,976 cycles
- Stage of operation: CL
- How discovered: O
- Nature of condition: F
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2021062735191

## Discrepancy

CLIMBING THRU FL 300. AUTOPILOT DISENGAGED AND UNABLE TO RE-ENGAGE. AUTOPILOT B ENGAGED OK. LATER IN FLIGHT WAS ABLE TO RE-ENGAGE AUTOPILOT A. GROUNDED - YES. REPLACED THE DFCS MCP PER B737-800 AMM 22-11-34/401. OP CHECKS REQUIRED. OPS CHECK OF MODE CONT PNL GOOD. ALL LLM TEST PASS REF AMM 22-11-34.

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