Abstract: A system for detecting electrolysis in an automobile system includes a probe, a microcontroller electrically coupled to the probe, a power supply configured to supply power to the microcontroller, a ground lead, and an optical indicator operationally coupled to the microcontroller. According to one embodiment, the microcontroller is configured to read a voltage across the probe and the ground lead when the probe is inserted into a coolant fluid and the ground is coupled to a ground source, analyze the voltage, and illuminate the optical indicator in response to the voltage analysis.