Home >> Land Rover >> 2021 >> Defender 110 >> Repair and Diagnosis >> General Information >> Specifications Index >> Diagnostic Trouble Code Index DTC: Audio Amplifier Module (AAM) -- Defender/L663 >> Diagnostic Trouble Code Index - DTC: Audio Amplifier Module (AAM) (G2804413) >> Description And Operation >> Audio Amplifier Module (AAM) >> DTC B1969-4B: External Sound Synthesis Module - Over temperature >> Possible Causes