Reasons for blocking:
* Low or poor quality transmission fluid
* Malfunction of torque converter lock-up solenoid
* Mechanical fault of the torque converter
* Problems with wiring or transmission control unit
* Faulty gear selector position sensor
How to unlock:
Check the fluid level and quality:
* Measure the transmission fluid level and, if necessary, add it to the “maximum” mark.
* Make sure to use the fluid recommended by the manufacturer.
Check the lock solenoid:
* Locate and disconnect the solenoid connector.
*Using a multimeter, check for power and ground at the connector.
*If there is no power or ground, there may be a problem with the wiring or transmission control unit.
Check the torque converter:
* Drain the transmission fluid and inspect it for metal shavings or foreign materials.
*If metal shavings are found, the torque converter may be damaged and need to be replaced.
Check the gear selector position sensor:
* Locate and disconnect the sensor.
* Using a multimeter, check if it is working correctly.
* If the sensor is defective, replace it.
Other possible solutions:
* Reset the transmission control unit.
* Disconnect and reconnect the battery terminal to reset the system.
* Check the operation of the starting and charging system.
If you are unable to unlock the transmission yourself, it is recommended that you take it to a qualified mechanic.