For anyone that has turned their avionics master switch on, and the Garmin G3X gives a PFD/GDU message akin to the following:
”Engine Interface configuration error.”
It’s important that we know what these messages really mean and if we are going to fly, then what we need to consider and weigh what the implications are in doing so.
Essentially, depending on the installation of the avionics, the reason for this is with software 9.00 or later, there is required a wiring and configuration change to the G3X Touch system and the GEA 24 EIS (Garmin Engine Adapter and Engine Indication System, respectively).
What does this mean to us? It means, that if we fly without the configuration and wiring changes, your fuel quantity will be inaccurate (more so than usual). Boiled down, don’t rely on your fuel quantity gauges if this is the case. Always use thorough fuel planning for each leg of the flight. Visually inspect the fuel on board prior to take-off for fuel management and flight planning to ensure adequate reserves, and refer to your aircraft POH or AFM for performance information.
The GEA 24 is part of the Engine Indication System (EIS), which monitors and displays key engine parameters such as oil pressure, fuel flow, and cylinder temperatures in Garmin's avionics suites. It acts as an interface between the engine sensors and the avionics display, ensuring that critical engine data is accurately shown to the pilot.
Here is a link to the advisory from Garmin: https://support.garmin.com/en-US/?faq=SQ5gCj4zw03wnJuyP8GWB6
Fun Fact: Did you know that airplane fuel gauges are only required to be accurate when the fuel tank is empty?
According to FAA regulations, fuel gauges on aircraft must indicate the fuel level correctly when the tank is completely empty, but there is no requirement for precision when the tank contains fuel. This may come as a surprise, but it highlights the importance of using tools and procedures to ensure accurate fuel management during flight, and especially preflight planning. Source: 14 CFR 23.1337(b)(1) of the Federal Aviation Regulations. This regulation specifies that "Each fuel quantity indicator must be calibrated to read 'zero' during level flight when the quantity of fuel remaining in the tank is equal to the unusable fuel supply."