The CMODs have an internal test circuit with indicators that you can use to locate failed DIMMs and verify a failed CPU after removing the CMOD from the server. The DIMM and CPU Fault Remind circuits hold an electrical charge for 10 minutes after power is removed from the server, allowing enough time to remove the CMOD and use the circuit LEDs to locate faulty components.
Each CMOD has a motherboard-mounted Fault Remind button. The button is part of the CMOD Fault Remind circuit. The circuit is charged and allows you to identify a failed DIMM or CPU after the CMOD has been removed from the server. You must remove the CMOD from the front panel to access the button.