Narrative:

While holding number one for takeoff we received an amber cas message; 'yd upper B fail.' we referred to the emergency abnormal checklist and as instructed selected yd upper a. The cas message turned cyan. We contacted the maintenance controller to discuss the malfunction and determine if the system could be MEL'd. We reviewed the MEL and determined that the system failure could not be MEL'd. We referred to the emergency abnormal checklist for the cyan message and read; 'do not dispatch.' we provided that information to the maintenance controller. He insisted that we try to pull the circuit breaker to reset the system so we could continue. As instructed; by maintenance; we pulled the circuit breaker and when it was reset the message went away. The controller advised us to continue. The message reappeared and the maintenance controller was busy looking for other solutions. In the mean time; tower advised us to return to the ramp because of pending departures. We returned to the ramp and made a logbook entry for the malfunction. We had no intention of departing with this malfunction. Our view of pulling the circuit breaker was simply to allow maintenance to trouble shoot the problem. Unfortunately; the maintenance controller's view was if the system reset we would be able to continue. The emergency abnormal checklist was clear; 'do not dispatch.' this malfunction requires a logbook entry and cannot be MEL'd. We were being pressured to clear a system malfunction by resetting the circuit breaker so we could continue.

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Original NASA ASRS Text

Title: CE750 Captain experiences a yaw damper failure while holding short for takeoff. An unsuccessful circuit breaker reset is attempted at the Maintenance Controllers suggestion; and the crew returns to the ramp for maintenance.

Narrative: While holding number one for takeoff we received an amber CAS message; 'YD UPPER B FAIL.' We referred to the Emergency Abnormal Checklist and as instructed selected YD Upper A. The CAS message turned Cyan. We contacted the Maintenance Controller to discuss the malfunction and determine if the system could be MEL'd. We reviewed the MEL and determined that the system failure could not be MEL'd. We referred to the Emergency Abnormal Checklist for the cyan message and read; 'Do Not Dispatch.' We provided that information to the Maintenance Controller. He insisted that we try to pull the circuit breaker to reset the system so we could continue. As instructed; by Maintenance; we pulled the circuit breaker and when it was reset the message went away. The Controller advised us to continue. The message reappeared and the Maintenance Controller was busy looking for other solutions. In the mean time; Tower advised us to return to the ramp because of pending departures. We returned to the ramp and made a logbook entry for the malfunction. We had no intention of departing with this malfunction. Our view of pulling the circuit breaker was simply to allow maintenance to trouble shoot the problem. Unfortunately; the Maintenance Controller's view was if the system reset we would be able to continue. The Emergency Abnormal Checklist was clear; 'Do Not Dispatch.' This malfunction requires a logbook entry and cannot be MEL'd. We were being pressured to clear a system malfunction by resetting the circuit breaker so we could continue.

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.