Summary
On March 8, 2018, an Embraer 170-100 aircraft experienced an in-flight indication related to the fuel system while cruising at Flight Level 380. The aircraft subsequently landed in Luxembourg, where maintenance personnel identified an electrical fault. The return flight was canceled, and the aircraft was operationally ferried to Warsaw the following day after repairs.
Event Details
During the cruise phase of flight, the Engine Indication and Crew Alerting System (EICAS) displayed the message "ENG 2 FUEL IMP BYPASS." The flight crew performed the actions prescribed by the applicable checklist and informed the Operations Control Center (OTC) via the ACARS communication system.
After landing in Luxembourg (LUX), the crew reported the fault recorded in the onboard computer to the OTC. The fault required inspection by a certified mechanic. Due to the unavailability of technical maintenance services at Luxembourg, the scheduled return flight was canceled. The aircraft was operationally repositioned to Warsaw the following day, after inspection and release to service per the Minimum Equipment List (MEL) by LOTAMS mechanics.
Technical Findings
Technical personnel arriving in Luxembourg conducted an analysis of the fault. The fuel filter on engine No. 2 was replaced in accordance with Aircraft Maintenance Manual (AMM) 73-21-05 Revision 56. During electrical measurements of the Fuel Measurement Unit (FMU) at connector P17, a short circuit was found between pins 12 and 13. Consequently, replacement of the FMU was deemed necessary.
Cause
The cause of the event was damage (short circuit in connector P17) in the FMU fuel system block.