Forti60F 7.4.5 Speed LED off

[nexustechnical]

We purchased some FortiGate 60F, some were on 6.4.6 and some were on 7.2, except for one FortiGate that was upgraded to 7.4.5. We noticed that the Fortigate on 7.4.5 has its speed LED of LAN 1-4 turned off occasionally (happened twice in 2 months of the Fortigate in use). We tried rebooting the FortiGate and factory reset, but the speed LED did not turn back on. 

We shut down the Fortigate and replaced it with a spare device, and the next day when we turned on the Fortigate, the speed LED of LAN ports is on again. With the device's LAN speed ports back up when turned on, the hardware test will pass, and RMA will most likely be rejected. Anyone experienced in the same or other versions, and what are the solutions? 

[AEK]

Normally when speed led is unlit it means not connected or 10Mbps.

Can you confirm the link is not 10Mbps?

Also try do the same test with both ends set to auto-negociate, not fixed speed.

[nexustechnical]

Internet access from the internal network is not available (apart from the Fortigate itself) when the cable is connected to the ports with speed LED off. 

Both ends are left with default settings, which is auto-negotiate

[DPadula]

Besides the LED off, are you seen any impact on FortiGate operation? Something like, packet drops, interface errors, etc?

[nexustechnical]

Not on Fortigate operation, but on internal network ping and DHCP fails to work. Internet access is also not available for internal network, while access of Fortigate through VPN from external is still available.