1Fitment: 6hp21 transmission gear position sensor repair board fits for 7 Series L1 L2 L3 L4 F02 Conductor Plate Tcu Ecu; Fit for A4 A6 A8 Q7 S4, fit for X1 X3 X5 Z4. 2Function: The 6hp21 transmission gear position sensor board is a common replacement part for vehicles experiencing transmission problems such as rough shifts, indecision, or slippage, help restore normal transmission function. 3Practical Sensor Part: The conductive plate is the bridge between the Tcu and the Ecu, enabling the vehicle's computer system to accurately control the transmission. Gear position sensors detect gear shift selection and transmitting the information to the Tcu. 4Material: Gear position sensor repair board is fabricated with aluminum alloy materials and advanced design techniques, can withstand harsh conditions and intense heat from the transmission. 5Installation: The installation of the 6hp21 gear position sensor board is simple and does not require modification of the car's existing wiring. For best results, professional installation is recommended.