Most EVO models have a redundant power supply with more than one removable power module in place. These allow for the failure of one module without interruption to the EVO.
If a power module is troubled, its light should turn red, and the EVO chassis should start alarming.
The EVO has a recessed button on the front of the chassis, either labeled "Alarm Reset" (not to be confused with "Reset") or with an icon of a speaker with a line through it. Pressing this will silence the alarm.
At this point, it's best to determine whether the trouble is with the power module, which is a simple part to replace, or the power supply itself.
To check this, first shut down the EVO. At the rear of the chassis, remove the power cord at the affected power module and then use the release tab to pull the module completely out, and note or photograph the sticker with the model and serial information for reference.
Sometimes simply reseating the module in the same slot will correct the behavior, but it's also a good idea to swap it with a working module in order to determine whether the trouble follows the module, stays at that slot, or goes away completely.
After swapping modules, power the EVO up, silence the alarm if needed, and check the power supply. If the same module fails in a different slot, it should be replaced. If the known-good module fails, the chassis may need to be serviced.
Contact us for any assistance and/or to find out what hardware coverage and replacement options are available.