Review Of How To Reset Check Engine Light Toyota Prius References. Web when your 2017 toyota prius's ecm (electronic control module), which is the vehicle's onboard computer, finds a problem in the electronic control system that it can’t correct, a computer turns on your check engine light. The dashboard of the car displays an indicator light that.

Hold down your car brake and press the power button to turn the car on. I disconnected the battery, still on. Web when your 2017 toyota prius's ecm (electronic control module), which is the vehicle's onboard computer, finds a problem in the electronic control system that it can’t correct, a computer turns on your check engine light.