It's a fact of life: Computers control your car. Automotive technology is both boon and bane. Computers control the operation of today's drivetrains, making possible higher levels of emission control and fuel economy while delivering the kind of performance drivers expect. Virtually every function of a car, including acceleration, braking, the transmission and even the suspension may be controlled by an array of circuits, sensors, wires and computer components.
Technological progress rarely comes without hiccups, though. Among the most worrisome reports in the news recently centers on the electronic throttle. Once directly connected to the accelerator via a cable or rod, the throttle now is more commonly connected to something similar to a rheostat that "tells" a computer what a driver's foot is doing.
Potential problems in such systems may arise from software errors or, according to some reports, difficult-to-reproduce instances of electromagnetic interference. Since designing a fail-safe computer system is impossible, manufacturers increasingly are building safety overrides into the most key area: braking. The brake override is standard in many cars with electronic throttles. Having faced the greatest amount of criticism recently, Toyota announced in February that it will make brake-override systems standard.
While safety issues are rare, they are of great importance when they occur. When purchasing a new car, those concerned about this issue should ask two questions: Whether the car has an electronic throttle, and, if it does, if it has a brake override system.
