Home › Land Rover › 2021 › Defender 90 › Repair and Diagnosis › Quick Lookups › Common Specs & Procedures › Diagnostic Trouble Code Index DTC: HVAC Control Module (HVAC) -- Defender/L663 › Diagnostic Trouble Code Index - DTC: HVAC Control Module (HVAC) (G2400894) › Description And Operation › HVAC Control Module (HVAC) › DTC B1419-93: Left Rear Cooled/climate seat Control Module - No operation › Possible Causes