578、Make sure that all the lights on the front of) the CMU do not come on.

910、If the indications do not clearly show that a fastener is loose, make a red line across the head and theadjacent material.

909、lf the circuit breaker opens, de-energize circuit.

908、If the airplane has a built in auxiliary power unit, describe it and explain how it fits in with the electricalsystem.

907、If the airplane experiences repeated failures of a pump at one location, there may be debris in the casedrain line, case drain hose or case drain hose quick disconnect that cannot be flushed by accomplishing thisprocedure.

906、If the air intake flap is not serviceable do the deactivation procedure of the air inlet valve. 如果进气口盖不能使用，则对进气口阀进行失效处理。

905、If one or more blades（叶片） are missing make an entry in the engine logbook如果一个或多个叶片丢失，请在发动机日志簿中进行记录

904、If it is possible that the temperature values will be more than the permitted limits, decrease the power.

903、If either of these devices is installed explain whether it is required equipment

902 、If an engine fire detection system is available. describe, give principle of operation, and explain how touse it.

901、If a supply shutoff valve was closed for less than five minutes ho maintenance is required and shutoffperiods are hot accumulative. 如果供应关闭阀关闭时间少于 5 分钟，则需要进行维护，关闭时间为热累积。