Possible reasons:
Mechanical problems:
*Low transmission fluid level
* Worn or damaged transmission parts (eg gears, synchronizers)
* Slipper clutch
*Hydraulic leaks
Electrical problems:
* Faulty shift solenoid
* Faulty gear selector position sensor
* Problems with the transmission electronic control unit (ECU)
Software problems:
* Errors in the transmission ECU software
Other possible reasons:
* Worn or dirty transmission fluid filter
* Presence of foreign objects in the gearbox
* Damaged driveshaft or CV joint
* Engine problems (such as low power or unstable rpm)
Troubleshooting Tips:
1. Check the level and quality of the transmission fluid.
2. Inspect the transmission for leaks or damage.
3. Use the OBD-II diagnostic scanner to read transmission-related trouble codes (DTCs).
4. Check the shift solenoids and shift position sensor for malfunctions.
5. Check the transmission ECU and update the software if necessary.
6. Replace worn or dirty transmission fluid filter.
7. Correct any mechanical or electrical problems found.
8. Consider flushing or replacing the transmission fluid.
Caution: Transmission repair is a complex task and should be performed by a qualified mechanic. Attempting to repair the transmission yourself may cause further damage.