Dell Precision 3930 Rack Service Manual page 76

However, if the computer fails the POST, the computer emits a series of LED codes during the start-up. The system LED is integrated on
the Power button.
The following table shows different light patterns and what they indicate.
Table 4. States Under Host BIOS Control
Amber LED state Fault Description Faults
1, 1 Bad MBD
1, 2 Bad MB, PSU or
cabling
1, 3 Bad MBD, DIMMS
or CPU
2, 1 CPU
2, 2 Motherboard:
BIOS ROM failure
2, 3 Memory
2, 4 Memory
2, 5 Memory
2, 6 Motherboard:
Chipset
3, 2 PCI / Video
3, 3 BIOS Recovery 1
76 Troubleshooting
BAD MBD – Rows A, G, H, I and J from table
12.4 of SIO Spec- Pre-POST indicators
Bad MBD, PSU or PSU cabling -Rows B, C and
D of table 12.4 SIO spec
Bad MBD, DIMMS or CPU- Rows F and K
from table 12.4 of SIO spec
CPU failure
Motherboard, covers BIOS corruption or ROM
error
No Memory/RAM detected
Memory/RAM failure
Invalid memory installed
Motherboard / Chipset Error
PCI or Video card/chip failure
Recovery Image not found
Recommendation for Tech Support
Make sure PSU stays off when this happen
or it might just be a tripping system. If truly is
the 1-1 blink code, replace MB.
Make sure all PSU cable, control and power
are all connected. Remove PSU and test
BIST button outside of the system first, if
failed, replace PSU. If not, install back the
PSU and test the BIST button again. If failed,
replace motherboard.
Make sure PSU stays ON when this happen
or it might just be a false alarm. If truly is the
1-3 blink code, replace MB.
Make sure a CPU is installed in primary
socket. Check for CPU gold pad dirt/finger
prints. Try a known good CPU on failing
system. If still cannot resolve issue, replace
motherboard.
Power off system and install RTC_RST
jumper. Remove jumper and power back on
to see if issue persist. Make sure system
stays ON and 2-2 code repeats when this
happen or it might just be a false alarm. If
truly is the 2-2 blink code, replace MB.
Make sure a supported DIMM is installed. Try
different DIMM slots. Try knonw good DIMM
stick. If still cannot resolve issue, replace
motherboard.
Make sure a supported DIMM is installed. Try
different DIMM slots. Try knonw good DIMM
stick. If still cannot resolve issue, replace
motherboard.
Make sure a supported DIMM is installed. Try
different DIMM slots. Try knonw good DIMM
stick. If still cannot resolve issue, replace
motherboard.
Power off system and install RTC_RST
jumper. Remove jumper and power back on
to see if issue persist. If yes, power off
system and remove coin cell battery. Install
back battery and power back on to see if
issue persist. If yes, replace motherboard.
Swap monitor/Video cable/GFX card. Try
GFX card only in slot 2 and slot 4. If not
resolved, replace motherboard.
Power off system and install RTC_RST
jumper. Remove jumper and power back on
to see if issue persist. If yes, power off