What does the ASR in Volkswagen Touran mean?
2 Answers
Definition of ASR: ASR stands for Anti-Slip Regulation (or Acceleration Slip Regulation). It is an active safety device in automobiles, also known as the Traction Control System. It prevents wheel slippage during acceleration, especially in high-powered vehicles, to maintain the stability of the vehicle's direction of travel. Function of ASR: Its primary purpose is to prevent the driving wheels from slipping during acceleration, particularly on special road surfaces with low friction such as rain, snow, hail, or ice. When the car accelerates, it controls the slip ratio within a certain range, thereby preventing rapid slipping of the driving wheels. Its functions are twofold: first, to improve traction, and second, to maintain the vehicle's driving stability. On slippery roads, a car without ASR is prone to wheel slippage during acceleration. Rear-wheel-drive vehicles may experience fishtailing, while front-wheel-drive vehicles may lose directional control. With ASR, the car either avoids or significantly reduces such phenomena during acceleration. During turns, if the driving wheels slip, the entire vehicle may drift to one side. With ASR, the vehicle follows the correct turning path. Most importantly, during turns, if the driving wheels slip, the entire vehicle may dangerously drift to one side, which is extremely hazardous on mountain roads. Vehicles equipped with ASR generally do not encounter this issue. Principle of ASR: When the driving wheels slip, ASR compares the rotational speeds of all wheels. The electronic system detects the slippage and immediately reduces the throttle intake, lowering the engine speed and thus reducing power output. It also applies braking to the slipping driving wheels. This ensures the most appropriate power output to minimize slippage and maintain tire grip on the road surface. Under ASR intervention, no matter how much throttle is applied, the system will output the optimal power for the conditions.
I've been driving this Touran for over five years, with the ASR button located right next to the gear lever. The manual calls it the Anti-Slip Regulation system. Essentially, it prevents wheel spin during acceleration, making it particularly useful for northern winters. Once during heavy snowfall, when starting on an icy slope, I clearly felt the system automatically braking the slipping wheels while keeping the engine RPM in check, allowing the car to climb up steadily. To deactivate it, you need to hold the button down, and a yellow icon will appear on the dashboard. But don’t turn it off casually—especially during high-speed cornering in the rain, as it can help correct your steering. If the ASR light stays inexplicably lit on the dashboard, chances are the wheel speed sensor is clogged with mud.
