Possible reasons for all automatic transmission indicator lights on an Opel to light up:
Electronics problems:
* Faulty automatic transmission control module (TCM)
* Problems with wiring or connectors
*Weak battery or problems with the charging system
Mechanical problems:
*Low transmission fluid level
* Wear or damage to internal automatic transmission components (such as gears, clutches or torque converter)
*Transmission fluid leak
Sensors and solenoids:
* Faulty vehicle speed sensor
* Faulty shift solenoids
* Faulty gear selector position sensor
Other possible reasons:
* Automatic transmission overheating
* Automatic transmission emergency operation mode
*Programming errors
* Vacuum leak in the vacuum lines of the automatic transmission control system
Recommended actions:
1. Check the level and condition of the transmission fluid.
2. Connect the OBD-II scanner and check for fault codes.
3. Visually inspect the automatic transmission for leaks or damage.
4. Check the battery and charging system.
5. Check the wiring and connectors associated with the automatic transmission.
6. Consult a qualified automatic transmission mechanic.