Overview

• JR East confirmed on July 9 that a fifth E8 series trainset stored at a depot has a defective auxiliary power supply unit
• Inspections revealed damaged semiconductor components in all five affected power units without a clear root cause
• Standalone operations of the E8 series remain suspended, preventing deployment of the latest high-speed rolling stock
• Yamagata Shinkansen service will continue on a reduced timetable with compulsory transfers at Fukushima station through the end of July
• JR East has grouped the defective trainsets by manufacturing batch to focus the ongoing defect investigation