Home >> Land Rover >> 2021 >> Defender 90 X >> Repair and Diagnosis (Single Page) >> General Information >> Specifications Index >> 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 B1D1B-87: Pneumatic Module - Missing message >> Possible Causes