What should be the first thing checked when an avionics failure is suspected?

When an avionics failure is suspected, the circuit breaker should be checked first because it plays a critical role in the operation of the avionics systems. If there is a failure, the circuit breaker could have tripped due to an overload, fault, or other electrical issue. Checking the circuit breaker helps to quickly determine if the failure is simply a result of power being cut off to the avionics.

If the circuit breaker is tripped, resetting it may restore functionality, allowing for further troubleshooting if necessary. This step is crucial, as ensuring that power is being supplied to the avionics is foundational before considering other potential issues such as navigation settings, power sources, or external connections. These components may be entirely operational, but if the circuit breaker is not engaged, the avionics will not function regardless of their individual conditions.