Reasons for automatic transmission locking:
*Low transmission fluid: Insufficient fluid levels cause clutch slippage and overheating of the transmission.
*Hydraulic control unit problems: Faults in the hydraulic unit can cause the system to lose pressure and lock up the transmission.
*Failure of mechanical components: Worn gears, shafts or bearings can cause the transmission to lock up.
* Electrical Problems: Faults in the wiring, sensors, or electronic control unit (ECU) can interfere with transmission operation.
*Mode switch problems: A faulty mode switch can cause the transmission to not operate properly.
Actions when the automatic transmission is blocked:
*Check transmission fluid level: Make sure the fluid level is within the correct range and that the fluid is clean.
* Scan your vehicle for trouble codes: Use an OBD2 scanner to check for trouble codes that may indicate the cause of the lockup.
* Check mechanical components: Check gears, shafts and bearings for wear or damage.
*Consult a mechanic: If you cannot determine the cause of the lock yourself, contact a qualified mechanic.
Precautions:
* Do not try to force change gears.
* Do not drive with the transmission locked as this may cause serious damage.
* Tow the vehicle to a repair shop.