Possible reasons why the automatic transmission goes backward when shifting forward:
Valve unit malfunction:
* Clogged or worn solenoids
* Malfunction of transmission fluid pressure sensors
* Valve block leakage
Problems with planetary gear:
* Worn or broken teeth
* Seized or faulty clutches
Torque converter malfunction:
* Wear or breakage of blades
*Transmission fluid leak due to faulty seal
Electronics problems:
* Faulty gear selector position sensor
* Malfunction of the electronic transmission control unit (ECU)
Other reasons:
*Low transmission fluid level
* Contaminated or spoiled transmission fluid
* Malfunction of drive shafts
Troubleshooting:
To fix the problem, you need to diagnose the gearbox at a car service center. A specialist will determine the exact cause of the malfunction and repair or replace the necessary parts.
Important: Do not continue to drive a vehicle with a faulty transmission, as this may cause further damage and costly repairs.