Home >> Land Rover >> 2021 >> Discovery R-Dynamic HSE >> Repair and Diagnosis >> General Information >> DTC Index >> Diagnostic Trouble Code Index DTC: Infotainment Master Controller/Infotainment Slave Controller (IMC/ISC) -- Discovery/L462 >> General Information >> Description And Operation >> Diagnostic Trouble Code Index - DTC: Infotainment Master Controller/Infotainment Slave Controller (IMC/ISC) (G1842475) >> DTC B1492-1A: Microphone #1 Input Signal - Circuit resistance below threshold >> Possible Causes