Intelligent speed assistance uses GPS data and traffic sign recognition cameras to determine the current speed limit. The system either warns the driver when they exceed the limit or actively reduces engine power to prevent the vehicle from speeding. It is mandated on new vehicles to improve road safety.
Heard on the job
The customer is complaining that the ISA keeps cutting power on the highway because it reads the frontage road speed signs.
Insider tip
Mechanics often get complaints about ISA systems misinterpreting signs; diagnosing it usually requires checking camera calibration and map data versions.