Final answer:
A FUEL MODE SEL FAULT light can be caused by various factors related to fuel mode selection in an aircraft. Possible causes include a faulty fuel mode selector switch, a malfunctioning fuel system component, or a communication error.
Step-by-step explanation:
A FUEL MODE SEL FAULT light can be caused by various factors related to fuel mode selection in an aircraft. This light typically indicates an issue with the fuel system or the fuel mode selector switch. Possible causes of this fault light include a faulty fuel mode selector switch, a malfunctioning fuel system component, or a communication error between the fuel mode selector and other systems.
For example, if the fuel mode selector switch is stuck in a particular position or fails to respond to commands, it can trigger the fault light. Similarly, if a fuel system component like a fuel pump or fuel valve malfunctions, it can lead to the activation of the FUEL MODE SEL FAULT light.
Correct troubleshooting and maintenance procedures are crucial to determine the exact cause of the fault light and rectify the issue.