Why doesn't the automatic transmission move when shifted to D gear and accelerating?

[McJack]

The reasons why an automatic transmission doesn't move when shifted to D gear and accelerating are as follows: 1. Insufficient transmission fluid. 2. Low internal oil pressure. 3. Incorrect gear switch signal. 4. Issues with the shift solenoid wiring or the solenoid itself. 5. Problems with the internal transmission actuators. Here is some extended information about automatic transmission gears: 1. P gear is the parking gear, used for long-term parking of the vehicle. 2. R gear is the reverse gear, engaged when the vehicle needs to move backward. 3. N gear is the neutral gear, engaged when the vehicle is parked for a short time without turning off the engine. 4. D gear is the drive gear; when the gear lever is in D gear, the vehicle automatically shifts gears based on throttle opening and speed data. 5. S gear is the sport mode, making the vehicle drive more sportily. 6. M gear refers to manual mode; when the gear lever is in M gear, shifting is done manually by the driver. 7. L gear is the low gear.