Possible reasons:
1. Problems with the gear shift cable:
* Worn or damaged cable
* Poor cable adjustment
* Cable contamination
2. Problems with the gear selector:
* Worn or broken selector
* Contamination or foreign objects
3. Mechanical problems with automatic transmission:
* Worn or damaged gears, gears or couplings
*Low transmission fluid level
4. Electronic problems:
* Faulty gear selector position sensor
* Malfunction of the automatic transmission electronic control unit (ECU)
5. Other possible reasons:
* Low level of lubrication in the gear shift mechanism
* Presence of foreign objects in the gear shift mechanism
* Damage to the clutch or brake band of the automatic transmission
Solution:
1. Check the shift cable:
* Make sure the cable is not frayed or damaged and is adjusted correctly.
* Replace or adjust the cable if necessary.
2. Check the gear selector:
* Make sure the selector is not worn, broken or dirty.
* Clean and lubricate the selector.
3. Check the automatic transmission mechanics:
* Make sure the transmission fluid is at the proper level.
* Check for leaks or damage. Make repairs if necessary.
4. Check the electronics:
* Scan the automatic transmission ECU for fault codes.
* Check the gear selector position sensor and automatic transmission ECU for signs of malfunction. Replace faulty components if necessary.
5. Eliminate other possible causes:
* Lubricate the gear shift mechanism.
* Remove foreign objects.
* Check the condition of the automatic transmission clutch and brake band.
Important:
To properly diagnose and troubleshoot the problem, professional assistance from an automatic transmission repair specialist may be required. Do not attempt to disassemble or repair an automatic transmission yourself unless you have the appropriate knowledge and experience.