Lenovo ThinkServer RD340 - Manual (Page 60)

2 - 7 System fan error LEDs
When a system fan error LED on the system board is lit, it indicates that the corresponding system fan is
operating slowly or has failed. To solve the problem, you might need to reinstall or replace the system fan.
See “Replacing a system fan” on page 156. If it is a system board problem, contact the Lenovo Customer
Support Center.
48 ThinkServer RD340 User Guide and Hardware Maintenance Manual