Home › Land Rover › 2021 › Defender 110 X-Dynamic HSE › Repair and Diagnosis › Quick Lookups › Common Specs & Procedures › Diagnostic Trouble Code Index DTC: Transmission Control Module (TCM) -- Defender/L663 › Diagnostic Trouble Code Index - DTC: Transmission Control Module (TCM) (G3187879) › Description And Operation › Transmission Control Module (TCM) - 8HP70/45 Transmissions › DTC P2545-86: Torque Management Request Input Signal "A" Range/Performance - Signal invalid › Possible Causes