Home >> Land Rover >> 2017 >> Range Rover Autobiography >> Repair and Diagnosis >> Quick Lookups >> DTC Index >> 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 P07D9-07: Gear 8 Incorrect Ratio - Mechanical failures >> Possible Causes