5v output short-circuit or overloaded.
Most common issues and how to fix them
1. Most likely one of your connected +5V sensors are damaged or short-circuited. Please check your wiring's. Detach all connected sensors, remove error code and check if the error code comes back.
2. Check internal +5V regulator
5V VRref voltage should always be ~5v.
MaxxECU wirings (downloads)
Please contact support if problem persist.