Incredible Check Engine Light Battery Problem Ideas. Find out here what to do next. The light is triggered when the car’s onboard computer, also known as the electronic control unit (ecu), detects a problem or malfunction with the engine or emissions control system.

There are a few reasons why your check engine light might be turning on. This is especially if the check engine light is being triggered by the ecu because the sensor just won’t detect the new battery. Flashing / red check engine light a red (rather than yellow/orange) or flashing light on your dash signals a serious issue that needs urgent attention.





