Home >> Land Rover >> 2021 >> Defender 110 S >> Repair and Diagnosis >> Quick Lookups >> Common Specs & Procedures >> Diagnostic Trouble Code Index DTC: Driver/Passenger/Rear Seat Module (DSM/PSM/RSM) -- Defender/L663 >> Diagnostic Trouble Code Index - DTC: Driver/Passenger/Rear Seat Module (DSM/PSM/RSM) (G2807246) >> Description And Operation >> Driver/Passenger Seat Module (DSM/PSM) - Left/Right >> DTC B155D-01: Seat Head Restraint Height Motor Drive - General electrical failure >> Possible Causes