Should You Turn On AOFF While Driving?

[Gael]

AOFF can be turned on while driving. AOFF is the switch for the auto start-stop function, which effectively reduces fuel consumption and minimizes engine idling to decrease carbon buildup. However, the AOFF function should be turned off when the vehicle is driving through water, as it may cause engine damage. The illuminated AOFF light indicates that the auto start-stop function is active. The start-stop system works as follows: when the vehicle stops due to traffic congestion or at an intersection, and the driver presses the brake pedal and shifts to neutral, the StartStop system automatically checks if the engine is idling, the transmission is in neutral, the wheel speed sensors of the anti-lock system show zero, and the battery sensor indicates sufficient energy for the next start. If all these conditions are met, the engine will automatically shut off.

[DelPenelope]

I've been driving for eight years, and whether to turn off the auto start-stop depends on the situation. During the morning rush hour traffic, the system repeatedly shuts off and restarts, making the steering wheel shake like a massage chair, so I just turn it off. But it's especially fuel-efficient when waiting at red lights in the city, with the dashboard showing it can save 0.8 liters of fuel per hour. It's important to turn it off during heavy rain—last year, the system suddenly restarted while I was driving through water, which gave me a scare. As for whether it damages the car, Old Zhang from the repair shop says the starters nowadays are reinforced, but you need to use AGM-enhanced batteries, as regular lead-acid batteries would be ruined in half a year.

[LincolnDella]

After researching this system, it essentially uses a 12V battery to maintain electrical operation. When the engine shuts off at a red light, brake assist will decrease by one-third, so never use it on long downhill slopes. The function is automatically disabled when the battery temperature is below 5°C; even if the button light stays on, don’t force it to activate. The most practical feature is for cars with AutoHold—after triggering the start-stop by pressing the brake pedal firmly, you can rest your foot. However, during cold starts when the engine oil hasn’t fully circulated, I usually manually turn it off for the first five minutes.

[DeNatalie]

After careful calculation of fuel costs, I dare to say: Start-stop saves you 500 yuan a year on gas, but replacing the battery costs an extra 800 yuan. It's simply not worth it for short commutes—my home to the office is just three kilometers, and the engine doesn't even warm up before arriving. The most annoying part is when the steering wheel suddenly vibrates and restarts while scanning the payment code in a mall parking lot, with cars behind honking like crazy. Now I've developed a habit: the first thing after ignition is to turn off the start-stop. If you want to save fuel, it's better to avoid slamming on the brakes a couple of times less.

[LaAmy]

Listen up, ladies: Never use auto start-stop with the AC on! When the engine shuts off, the AC only blows air, which can ruin your makeup in summer heat. It's even worse when traveling with kids—rear safety seats lack ventilation, and the jolt from auto restart often wakes sleeping children. Modern EVs are smarter, using the traction battery to maintain AC. For fuel-powered cars, I recommend buying an auto start-stop deactivator—just plug it into the OBD port for permanent deactivation (around 80 yuan), much easier than manually disabling it every ignition.

[MiaLynn]

Tested the start-stop strategy of a certain German car: it only activates when the seatbelt is fastened, the door is closed, and the coolant temperature is above 70°C. Each restart produces emissions equivalent to 10 seconds of idling pollution, but stopping for 30 seconds can offset it. What really should be shut down are old diesel vehicles, whose black smoke particulate concentrations double. From an environmental perspective, 48V mild hybrids are more favorable, as just 0.3 kWh can support two minutes of operation. It is suggested to legislate that automatic start-stop systems can be manually disabled, as the control over safety should ultimately lie in the driver's hands.