Home >> Land Rover >> 2020 >> Range Rover Autobiography >> Repair and Diagnosis >> Quick Lookups >> Common Specs & Procedures >> Diagnostic Trouble Code Index DTC: HVAC Control Module (HVAC) -- Range Rover/L405 >> General Information >> Description And Operation >> Diagnostic Trouble Code Index - DTC: HVAC Control Module (HVAC) (G2164849) >> DTC B1966-87: Left Rear Door Armrest Heater - Missing message >> Possible Causes