Home >> Land Rover >> 2017 >> Range Rover Autobiography >> Repair and Diagnosis >> Transmission >> Transmission Control Systems >> Diagnostic Trouble Code Index DTC: Transmission Control Module (TCM) -- Range Rover/L405 >> Diagnostic Trouble Code Index DTC: Transmission Control Module (TCM) >> Description And Operation >> DTC P177D-07: Transmission Friction Element A or E - Mechanical failures >> Possible Causes