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This error is the result of either one or both of the Orange and Yellow data wires failing to allow the Arduino and Display to communicate with each other. Here are the steps you should take to troubleshoot the problem:
Check The Display Diagnostics Bar #
- The Pin 18(TX) wire (Yellow on Arduino, Yellow on Display) is communicating data from the Arduino to the Display properly.
- The Pin 19(RX) wire (Orange on Arduino, Blue on Display) is not creating a successful connection.

- Either the Pin 18(TX) wire or the Pin 19(RX) wire, or both, are not creating a successful connection
- The DISP -> ARD error checker relies on a positive ARD -> DISP connection, so it could be either wire.

Troubleshooting Steps #
- Double check the wiring from the wiring guide located here. Make sure that the Pin 18 (TX) wire is going to the Yellow wire of the Display, and the Pin 19 (RX) wire is coming from the blue wire of the Display.
- Make sure the wires have a good connection. The female Display wire harness has very tight connectors – sometimes, it is possible to insert the male Arduino side connectors without getting actual contact. You should feel a small bit of resistance as they slide together.
- Check that the Arduino is running the startup sequence when powered on – when first booted, the Arduino’s feedback LED (near the USB connector) will blink every second in a heartbeat. That means it’s waiting for a positive connection from the display.
- Try replacing the data wires, one at a time, with the Green ‘Spare’ wire that comes with the Kit, to rule out a bad wire.
- Make sure that the Arduino and Display are both on the same firmware version.
Still Stuck? #
If you’re still having errors, it is possible you have either a bad Display or a bad Arduino.
Feel free to contact us with any questions or a second opinion.