Possible reasons why the automatic transmission stopped moving:
Mechanical problems:
*Failure of friction discs
* Worn or broken gears
* Damage to shafts or bearings
*Low or contaminated transmission fluid
* Torque converter problems
* Oil filter clogged
Electrical problems:
* Faulty sensors (eg speed sensor, throttle position sensor)
* Wiring problems (breaks, short circuits)
* Malfunction of the electronic control unit (ECU) of the transmission
Other reasons:
* Engine problems (low power, misfire)
* Clogged catalytic converter
* Timing belt or chain slippage
* Faulty transmission (eg differential)
* Transmission overheating
Additional signs indicating problems with the automatic transmission:
* Jerks, jerks or delays when shifting gears
* Strange noises (buzzing, grinding, knocking)
*Transmission fluid leaking or smelling
* Transmission fault indicator on the dashboard lights up
* Difficulty changing gears or starting from a stop