Power Supply Unit (PSU) Issue¶
What is a PSU?¶
A Power Supply Unit (PSU) gives power to the server. If the PSU fails, the server may not start or may shut down.
PSU error messages usually look like:
- PSU0001
- PSU0002
- PSU0003
Common PSU Problems¶
You may see:
- Server not turning ON
- Amber (orange) light on PSU
- Power redundancy warning
- No display (No POST)
First checks¶
- Make sure the power cable is connected tightly
- Check the power socket or PDU
- Press the server power button
- Check if any PSU warning is shown in iDRAC
Troubleshooting Steps¶
Step 1: Check Cables¶
- Remove and reconnect the power cable
- Make sure PSU is fully inserted into the server
Step 2: Swap the PSU¶
If the server has two PSUs:
- Swap the PSU with the other slot
- If the problem moves → PSU is bad
- If the problem stays → board or motherboard issue
⚠️ Remove only one PSU at a time
Step 3: Check PSU Type¶
- Both PSUs must be same model
- Wattage must be enough for server hardware
- After CPU/GPU upgrade, old PSU may not be enough
Step 4: Check PSU LED Light¶
| LED Color | Meaning |
|---|---|
| Green | PSU is working |
| Blinking Green | PSU firmware update |
| Blinking Amber | PSU problem |
| No Light | No power connected |
Replacing a PSU¶
If the server has two PSUs (redundant), you do NOT need to shut down.
Remove PSU¶
- Unplug power cable
- Press release latch
- Pull PSU out slowly
Insert New PSU¶
- Slide new PSU into slot
- Connect power cable
- Wait a few seconds
- Check LED → should be green
Important Safety Notes¶
- Never remove both PSUs at the same time
- Use same type PSU only
- PSU firmware update causes downtime
If Problem Still Exists¶
- PSU may be failed
- Or motherboard / power board issue
- Contact technical support
Summary¶
✔ Check cables
✔ Check power source
✔ Swap PSU
✔ Check LED light
✔ Replace PSU if needed