# SDR ASAA2019100293869

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: September 30, 2019
- Submitted: October 2, 2019
- Operation: Air carrier
- Aircraft: [N560AS](https://openairdocs.org/aircraft/N560AS), registered now
- Make and model: Boeing 737890
- Aircraft serial: 35179
- Aircraft time: 50,057 hours, 14,978 cycles
- System (JASC): [2230 · Auto Throttle System](https://openairdocs.org/jasc/2230)
- Part: Autothrottle Sys
- Condition: Malfunctioned
- 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/ASAA2019100293869

## Discrepancy

AUTOTHROTTLE WILL ENGAGE, BUT DISENGAGES AFTER ABOUT 3 SECS, ANY MODE, EITHER AUTOPILOT ENGAGED OR NO A/P ENGAGED. GROUNDED - YES. REF B737-800 FIM 22-31 TASK 801 A/T BITE PROC., FOUND ASM-1 FAIL ON DISCREPANCY FLIGHT IN FAULT REVIEW. #1 THROTTLE WON'T MOVE DURING INTERACTIVE SERVOMOTOR TEST. RESET POWER TO SYST BY PULLING, THEN RESETTING A/T DC1 C/B. A/T OPS NRML PER FIM 22-31 TASK 801 - CURRENT STATUS & INTERACTIVE THROTTLE TESTS OPS NRML - NO FAULTS. BOTH THROTTLES MOVE TOGETHER AND SMOOTHLY.

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