2022年9月，有飞机在航前启动过程中，机组反应起动左发成功后，EGT红标线不消失，第一次无法接电，预计1分钟后自动关车，第二次启动EGT红标线消失慢 。
译码分析看左发未达到慢车稳定的情况下，开了空调组件，导致发动机功率损失，转速无法进一步增加，后由于无法稳定，导致掉转速。再次启动在达到慢车稳定转速后，接组件正常。
关于启动红线的说明：启动中出现红线，达到稳定慢车转速后才会消失。红线不消失，表示发动机没到达稳定的慢车转速。
关于机组操作的要求。
波音回复
热启动由N2 and P3 rates来设定，当一旦探测到热启动，将锁定直到启动手柄放CUTOFF位，并导致EGT闪烁。在启动过程中如果发生引气释放，这可能导致发动机更热或者超过启动门限。
In the meantime, if Hainan Airlines has not already done so, Boeing recommends Hainan Airlines perform FIM 80-05 Task 801 (Engine Start, EGT Indication Flashing or Engine Had an Automatic Shutdown). As noted in the FCOM Engine Start Procedure, the aborted engine start checklist should be performed if EGT quickly nears or exceeds the start limit. Also, the FCOM Engine Start Procedure states that PACKS should be OFF.
The engine hot start detected bit is set during starting if the EGT starting limit is exceeded, or if the EEC detects a stall based on N2 and P3 rates. Once set, the hot start bit will stay latched until the start lever is moved to CUTOFF. This bit is what causes the displays to flash the EGT digital readout, indicating a hot start. If there is bleed air extraction from the engine while it’s being started, that could cause the engine to run hotter and potentially exceed the start limit.
Regarding the IDG connection, there is a bit set by the EEC when engine is at an idle speed that can accommodate the load of the generator. Boeing suspects the IDG would not be able to operate until this bit is true.