Whenever MTune detects an "tune problem", the configuration problem detected! text label will blink in red to notify the user of an issue that needs to be taken cared of.
In the above example, MTune detects an error caused by setting 2 inputs as the the same source, in this case two vehicle speed (front), which can cause all kind of weird problem, as you might imagine...
•Pulse function used on 2 inputs.
•Output set on an unavailable output.
•Output function used on more than 4 outputs.
•No secondary injector outputs.
•Ignition cylinder angle trim problem.
•Memory almost full / fragmented
Configuration problems detected and how to solve them