Mechanical reasons:
*Lack or contamination of transmission fluid
* Wear of clutches or steel discs
*Hydraulic pump problems
* Oil filter clogged
* Damage to oil lines
* Wear of solenoids
* Faulty gear selector position sensor
Electrical reasons:
* Malfunction of the electronic control unit (ECU)
* Open circuit or short circuit in electrical wiring
* Malfunction of wheel speed sensors
* Problems with the battery or alternator
Software problems:
* Errors or failures in the ECU firmware
*Software update not completed properly
External factors:
* Extreme loads on the drivetrain (such as towing heavy loads)
* Late service
* Changing the gear ratio of the main pair
*Additional installation of equipment such as winches
Other reasons:
* Condensation in transmission fluid (in cold weather)
* Wear of torque converter clutch units
* Damage to the automatic transmission housing
* Wear of gears or bearings
* Violation of regulations