What do the plus and minus signs on an automatic transmission mean?
2 Answers
Automatic transmission plus and minus signs indicate manual mode. In manual mode, the driver can manually upshift or downshift, similar to driving a manual transmission vehicle where the car won't automatically shift gears. Typically, only automatic transmissions with manual mode (often called "manumatic" or "Tiptronic" transmissions) feature these symbols, with the letter "M" usually appearing between the plus and minus signs. The vehicle can be switched to manual mode at any time without restrictions like speed or RPM - the transmission will automatically match the appropriate gear based on real-time vehicle speed. Manual mode is commonly used for situations like uphill/downhill driving, overtaking, starting on icy/snowy roads, or in heavy traffic. When switched to manual mode, the car's display will show the current gear (e.g., D1 for 1st gear, D2 for 2nd gear, and so on).
I've been driving for over a decade and I'm very familiar with those plus and minus signs on automatic transmissions. That's the manual mode function, which allows you to temporarily control the gears. The plus sign is pressed to shift up one gear, suitable for flat roads or when accelerating – shifting up at higher RPMs makes the car smoother and more fuel-efficient. The minus sign is pressed to shift down one gear, ideal for climbing hills or overtaking, instantly increasing engine power to give the car more punch. Normally, automatic transmissions handle gear changes themselves, but with the plus/minus signs, you can intervene manually. For example, on long descents, downshifting uses engine braking to reduce brake wear and prevent overheating. I tried this on mountain roads a couple of years ago, and the results were excellent, improving safety too. But don’t press randomly—operate only at appropriate speeds. Downshifting too quickly can damage the engine, and the manual explains the specific steps. Overall, this feature is quite practical. Beginners should familiarize themselves with the car’s manual before driving, and when using an automatic transmission, don’t forget to flexibly use the plus/minus signs to control the rhythm.
