On QFX10002/PTX1000 devices PEM might fail with an alarm generated for "EEPROM read failed".  This KB explains the steps to troubleshoot this alarm.

The below alarm will be seen on the device QFX10002:-
 

On PTX1000

alarmd[5855]: Alarm set: PS SFXPC color=RED, class=CHASSIS, reason=FPC0: PEM 3 EEPROM read failed
craftd[5856]: Receive FX craftd set alarm message: color: 1 class: 100 object: 75 slot: 3 silent: 0 short_reason=PEM 3 EEPROM failur long_reason=FPC0: PEM 3 EEPROM read failed id=486540107 reason=486539264
craftd[5856]: Major alarm set, FPC0: PEM 3 EEPROM read failed
 
Rarely a Power trip may occur in the connected External power source.

Please follow the below steps to troubleshoot this issue:-
 

Step-1:-  Reseat the affected and check if the alarm clears.
 
Step 2:- Please swap the affected PEM with the working one and check if the alarm moves to another slot or stays in the same slot. This can help narrow down whether the issue is on PEM or chassis.
 
Step 3:- If the alarm stays on the same slot even after swapping the affected PEM with the working one then Power cycle the device to clear all transient hardware issues on the chassis which might have caused this alarm. If the issue continues even after the Power cycle then please contact JTAC for more help.
 
Step-4:- If the Alarm moves to another slot after swapping then the issue is with PEM and it needs to be replaced. Please contact JTAC to process an RMA for the PEM.