Technical Tip: On-Site Guide for Identifying a Faulty PSU in a FortiGate Firewall

This article focuses on diagnosing PSU failures in FortiGate firewalls, covering both hot-swappable PSU devices and devices with motherboard-fixed PSUs. It is designed for IT professionals and technicians with physical access to the equipment.

1. Identifying common signs of PSU failure: Check the PSU if the FAN is functional and check if any smoke signs.
2. Performing basic hardware checks: Check the Hardware to ensure it has not been damaged physically. Check if something like dust or any kind of unsupported materials are found on the PSU backside and check if any sign of water drops or moisture etc, found.
3. LED indicators for verification: Check the status of LED indicators, if there is any kind of LED light. It is supposed to be No-light, Green-light, Red-light and Amber-light.
4. Check the Power Source: Ensure that the power outlet supplying the Power (it can be Direct Power-DC or Alternate Power-AC backup power) to the affected PSU is functional by testing it with another plug/socket. Try to switch the power cable to another available socket/plug.
5. Inspect the Power Cable: Verify that the power cable connected to the non-working PSU is in good condition and properly connected. Sometime, just pullout and inserting back the power cable can helpful. Try to replace the power cable
6. Verify Power Unit: Check the power supply unit. If it is providing power to some other connected devices, the easy way is to connect  laptop or mobile charger into the same Power Unit/Source and verify if there is power.
7. Check if the PSU really needs to be replaced: Hard swap (don't need to power down the device) can be replaced with correct model part number using the proper screw-draw tools, and motherboard fixed this needs to be RMA, because it cannot be replaced.

After following these steps, if the PSU looks okay, the next step is to log-in into the FortiGate and run some diagnose commands.

Provide the output of the commands described in the following articles:

• Troubleshooting Tip: False positive power supply failure and temperature error logs on FortiGate
• Technical Tip: How to check power supply details for FortiGate 100/101E and 200/201E series models