Real-Time Clock (Rtc Reset); Flashing The Bios - Dell OptiPlex 7090 Service Manual

Table 31. Diagnostic LED status (continued)
Blinking pattern
2 6
3 1
3 2
3 3
3 4
3 5
3 6
3 7
4 1
4 2

Real-Time Clock (RTC Reset)

The Real Time Clock (RTC) reset function allows you or the service technician to recover Dell Inspiron, systems from No
POST/No Power/No Boot situations. The legacy jumper enabled RTC reset has been retired on these models.
Start the RTC reset with the system powered off and connected to AC power. Press and hold the power button for thirty (30)
seconds. The system RTC Reset occurs after you release the power button.

Flashing the BIOS

About this task
You may need to flash (update) the BIOS when an update is available or when you replace the system board.
88 Troubleshooting
Problem description
System board error, chipset error, clock
failure, gate A20 failure, super I/O failure,
keyboard controller failure
CMOS battery failure
PCIe or video card/chip failure
BIOS recovery image not found
BIOS recovery image found but invalid
Power Rail Failure: EC ran into power
sequencing failure.
Flash corruption detected by SBIOS
Intel ME (Management Engine) time-out
error
Memory DIMM power rail failure
CPU power cable connection issue
Suggested resolution
● Flash latest BIOS version.
● If problem persists, replace the
system board.
● Reset the CMOS battery
connection.
● If problem persists, replace the
RTS battery.
● Replace the system board.
● Flash latest BIOS version.
● If problem persists, replace the
system board.
● Flash latest BIOS version.
● If problem persists, replace the
system board.
● EC ran into power sequencing
failure.
● If problem persists, replace the
system board.
● Flash corruption detected by
SBIOS.
● If problem persists, replace the
system board.
● Timeout waiting on ME to reply
to HECI message.
● If problem persists, replace the
system board.
● Run PSU BIST.
● Remove and reconnect power
cables.
● If problem persists, replace the
system board or PSU based on
diagnostics run.