Narrative:

Flight was descending into ZZZ via the ZZZZZ3 arrival. Passing 11;000 [feet] on the descent; the autopilot mode control panel locked up. All mode control panel displays showed 888. All mode control inputs; heading; speed; altitude; became inoperable. Autopilot and auto-throttles failed. The altitude alert sounded continuously. Aircraft was then flown via raw data. Pilot monitoring informed ATC we lost the mode control panel. ATC directed us to descend and maintain 3;500 [feet]; thus removing all the crossing altitudes associated with the arrival. ATC also started vectoring us.after things settled down; pilot monitoring consulted QRH and as we suspected; there was not a nnc (non normal checklist) that addressed this scenario. During the descent; we became concerned about the reliability of the IAS [indicated airspeed]. When trying to slow it; seemed that the IAS was not responding normally. Crossing checking all systems; captain; first officer; [and] standby showed IAS was same. As we finally slowed and started to configure for the approach; the IAS indications started to respond normally. We received vectors for ILS xxr at ZZZ. Approach was flown via raw data and landing was uneventful. After blocking in; mx control was informed and mode control panel discrepancy entered in logbook. Local mx performed a hard reboot of aircraft; total power down and power up. This cleared the fault and logbook was cleared. We completed the last leg without further incident.note: the altitude alert sounded continuously from the time of mode control panel failure to aircraft power down. Reflecting on the incident; I think if it were to happen again I would have declared an emergency so as to give us more time. Also I think it would help ATC understand just how much our workload increased. I don't think we communicated to the controller just how busy we were because of this malfunction.

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Original NASA ASRS Text

Title: B737 Captain reported a mode control panel failure led to distraction and high workload.

Narrative: Flight was descending into ZZZ via the ZZZZZ3 Arrival. Passing 11;000 [feet] on the descent; the Autopilot Mode Control Panel locked up. All Mode Control Panel displays showed 888. All mode control inputs; heading; speed; altitude; became inoperable. Autopilot and auto-throttles failed. The altitude alert sounded continuously. Aircraft was then flown via raw data. Pilot Monitoring informed ATC we lost the Mode Control Panel. ATC directed us to descend and maintain 3;500 [feet]; thus removing all the crossing altitudes associated with the arrival. ATC also started vectoring us.After things settled down; Pilot Monitoring consulted QRH and as we suspected; there was not a NNC (Non normal checklist) that addressed this scenario. During the descent; we became concerned about the reliability of the IAS [Indicated Airspeed]. When trying to slow it; seemed that the IAS was not responding normally. Crossing checking all systems; Captain; First Officer; [and] Standby showed IAS was same. As we finally slowed and started to configure for the approach; the IAS indications started to respond normally. We received vectors for ILS XXR at ZZZ. Approach was flown via raw data and landing was uneventful. After blocking in; MX Control was informed and Mode Control Panel discrepancy entered in logbook. Local MX performed a hard reboot of aircraft; total power down and power up. This cleared the fault and logbook was cleared. We completed the last leg without further incident.Note: the altitude alert sounded continuously from the time of Mode Control Panel failure to aircraft power down. Reflecting on the incident; I think if it were to happen again I would have declared an emergency so as to give us more time. Also I think it would help ATC understand just how much our workload increased. I don't think we communicated to the controller just how busy we were because of this malfunction.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.