Home >> Land Rover >> 2021 >> Defender 90 X >> Repair and Diagnosis (Single Page) >> General Information >> Specifications Index >> Diagnostic Trouble Code Index Vehicles With: MHEV, DTC: Battery Energy Control Module (BECM) -- Defender/L663 >> Diagnostic Trouble Code Index - Vehicles With: MHEV, DTC: Battery Energy Control Module (BECM) (G2430860) >> Description And Operation >> Battery Energy Control Module (BECM) - Mild Hybrid Electric Vehicle (MHEV) >> DTC U0077-88: Control Module Communication Bus "E" Off - Bus off >> Possible Causes