Precision 7920 Tower Fan Error Message after Sleep Cycle

Precision 7920 Tower systems may present a FB0 Fan does not respond correctly failure on power on.

Fan failure warning

You might encounter a Flex Bay fan failure massage on your Precision 7920 Tower after rebooting the system after waking from a sleep state. (Figure 1.)

Figure 1. - Flex Bay Fan Error

Cold booting the system and running the ePSA system diagnostic from the F12 one time boot menu will resolve the issue in most cases.

Repair

If your system is BIOS revision 1.1.4 or lower and there is no Optional Flex Bay fan installed in the system, you may need to enter the system setup (F2 at boot) and disable all the optional Flex Bay fans in the BIOS under Systems Configuration, HDD Fans, to prevent this error on systems that are not Flex Bay fan equipped. (Figure 2.)

Figure 2. - Flex Bay (HDD Fans) Fans in the BIOS

NOTE: After making this BIOS change and restarting, the system will automatically turn back on any of the fans that are supposed to be active.

Solution

Flashing the system BIOS to revision 1.1.5 (Available 29 November 2017) or newer from the Dell Support Website/Drivers & downloads will resolve this issue. Choose BIOS from the Category drop-down menu to find the latest available BIOS update.

NOTE: After updating the BIOS, you will then need to re-enter System Setup and disable any optional Flex Bay fans under Systems Configuration/HDD Fans that were enabled during the BIOS update.