Home >> Land Rover >> 2021 >> Defender 90 X-Dynamic S >> Repair and Diagnosis >> General Information >> Specifications Index >> Diagnostic Trouble Code Index DTC: Gateway Module (GWM) -- Defender/L663 >> Diagnostic Trouble Code Index: Gateway Module (GWM) (G2801686) >> Description And Operation >> Gateway Module (GWM) >> DTC U0001-88: High Speed CAN Communication Bus - Bus off >> Possible Causes