What are the two main functions used by the ATC system to control traction?

The correct answer reflects the two critical functions of the Automatic Traction Control (ATC) system, which are differential braking and electronic engine control. These functions work together to optimize vehicle traction and stability, particularly in varying road conditions.

Differential braking refers to the ability of the ATC system to engage the brakes on one or more wheels that begin to spin faster than others due to loss of traction. By selectively applying the brakes to these wheels, the system helps restore grip, allowing the vehicle to maintain better control and stability.

Electronic engine control complements this by managing engine power output. When the system detects that a wheel is losing traction, it can reduce engine power to prevent further wheel spin. This interaction between adjusting braking and regulating engine power is essential for maintaining optimal traction and enhancing driving safety.

Other choices, while they may involve vehicle performance and maintenance, do not accurately represent the primary functions of the ATC system. For instance, tire inflation and wheel alignment are important for overall vehicle safety and efficiency but are not specific functions of traction control. Similarly, while brake pad adjustment and wheel sensors play roles in broader braking systems, they are not key components of traction control strategy like differential braking and electronic engine control are.