Building Custom Arduino-Controlled Gauges for a Mazda Miata

The beauty of the Mazda Miata is in its simplicity. You get two seats, four wheels, a modest engine, rear-wheel drive, and not much else. That’s what makes it so desirable to sports car purists, and the lack of superfluous equipment keeps it lightweight and nimble. While the newer models certainly have some modern tech equipment, the fanciest thing my first generation “NA” model had was FM radio. Droo also has an NA Miata, and decided to modernize it with a digital Arduino-controlled dashboard.

We’ve actually seen Droo’s 1993 Mazda Miata before, when he posted about a project that added an Arduino-controlled touchscreen in the center of the dashboard to monitor and control various parts of the car. That touchscreen could be used to start the engine, log performance data, change interior LED lighting colors, and even adjust the suspension. Now he’s gone even further by completely replacing the original gauge cluster with custom digital LCD screens.

The new gauge cluster seems to have one large LCD screen that shows through in four places: where the speedometer was, where the tachometer was, where the oil pressure gauge was, and where the warning lights were. Those are controlled by an Arduino Due microcontroller development board, which receives data from the car’s CAN (Controller Area Network) bus. That data includes current speed, engine RPM, temperature, fuel level, oil pressure, and so on.

With this setup, Droo can display that data graphically on the LCD screens in whatever style he likes. He’s demonstrated that with two different styles: a JDM (Japanese Domestic Market) version that looks roughly stock, and a Sport Mode version that has a much more digital aesthetic. In both cases, the graphics are drawn programmatically, which is easier for the Arduino to process than bitmap images. The results look fantastic, and this setup gives Droo nearly endless customization options for his car.