# SDR ASAA2023041242816

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: April 12, 2023
- Submitted: April 17, 2023
- Operation: Air carrier
- Aircraft: [N479AS](https://openairdocs.org/aircraft/N479AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 60576
- Aircraft time: 27,457 hours, 8,559 cycles
- System (JASC): [2210 · Autopilot System](https://openairdocs.org/jasc/2210)
- Part: Pressure Switch
- Part number: 211C223527
- Part serial: F028882AC
- Condition: Failed Insp
- Location: Lt Mlg Ww
- Stage of operation: CL
- How discovered: V
- Nature of condition: J
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2023041242816

## Discrepancy

ON CLIMBOUT AUTOPILOT B WAS SELECTED AFTER A COUPLE OF SECONDS IT DIS-ENGAGED. CONSULTED QRH AND AUTOPILOT B WAS SELECTED AGAIN AND IT DIS-ENGAGED AFTER A COUPLE OF SECONDS. AUTOPILOT A WAS SELECTED AND IT WORKED NORMAL. GROUNDED - YES.  REMOVED & REPLACE BOTH SOLENOIDS AT A/P ACTUATOR A (M943). IAW B737-900 AMM 22-11-12-400-801.

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