This article explains 'PEM X Temp Sensor Hot' alarm and course of action for these alarms.

Below alarm/logs will be seen for any PEM that has Temperature sensor alarm.

Oct 20 21:28:43.421 router-name alarmd[32559]: Alarm set: PS SFXPC id=722468939, color=RED, class=CHASSIS, reason=PEM 1 Temp Sensor Hot

Oct 20 21:28:43.423 router-name craftd[31803]: Major alarm set, PEM 1 Temp Sensor Hot

Oct 20 21:28:53.360 router-name alarmd[32559]: Alarm cleared: PS SFXPC id=554696779, color=YELLOW, class=CHASSIS, reason=PEM 1 Not Powered

Oct 20 21:28:53.361 router-name craftd[31803]: Minor alarm cleared, PEM 1 Not Powered

Oct 20 21:28:53.365 router-name alarmd[32559]: Alarm cleared: PS SFXPC id=722468939, color=RED, class=CHASSIS, reason=PEM 1 Temp Sensor Hot

1. When such alarms are seen for PEM (or any FRU), check for the router environment for any blockage/obstacle in air flow, dust.
2. If everything is found, clean and still the alarms are appearing, it could be an indication of Temperature Sensor failure. In this case, Pls reach out to JTAC for PEM replacement