The Precision T3500/T5500/T7500 Workstations are equipped with diagnostic and status lights. There are numbered lights, 1-4, and the power button also serves as a status indicator. Depending on the status of the system, the power button light may be green or amber and may be off, solid, or blinking. There are five total power button light states:
Four (4) single color LEDs are incorporated on the front control panel to serve as a diagnostic aid for troubleshooting systems exhibiting No Post/ No Video symptoms. The LEDs do NOT report runtime errors. The LEDs are numbered 1-4 and are located on the front panel, between the audio jacks and the front USB ports. Additionally, there are LEDs to indicate network and hard drive activity. You can see these LEDs in the image below.
Each LED has two possible states of OFF or ON. The most significant bit is labeled with the number 1, and the other three are labeled 2, 3, and 4, as you go down or across the LED stack. The normal operating condition after POST is for all four LEDs to be ON and then turn off as the BIOS hands control over to the Operating System.
The information provided by the diagnostic indicators helps to indicate the functional state of the system. If you require additional assistance in determining the troubleshooting process of your system, see the techncial support contact information at the bottom of the page.
State |
LED Pattern ( 1 2 3 4 ) |
LED Description |
Power LED |
State Assignment |
State Description |
Pb0a |
|
1- Off 2- Off 3- Off 4- Off |
|
System Unplugged |
System is not plugged into AC, PSU is not plugged into system board, or control panel not connected to system board. |
Pb0b |
|
1- Off 2- Off 3- Off 4- Off |
|
ACPI S0; Normal Operation |
System is on with no failures detected. This is actually a BIOS controlled state and is also S0e. |
Pb0c |
|
1- Off 2- Off 3- Off 4- Off |
ACPI S1 |
Windows Standby State. |
|
Pb1 |
|
1- Off 2- Off 3- Off 4- Off |
|
ACPI S4 or S5 |
Hibernate or Soft off. System plugged in, but either turned off or in Windows Hibernation State. |
Pb2 |
|
1- Off 2- Off 3- Solid 4- Off |
- |
Reserved |
Reserved |
Pb3 |
1- Off 2- Off 3- Solid 4- Solid |
ACPI S3 |
Suspend to RAM Windows Standby State. |
||
Pb4 |
|
1- Off 2- Green 3- Off 4- Off |
- |
Reserved |
Reserved |
Pb5 |
1- Off 2- Green 3- Off 4- Green |
- |
Reserved |
Reserved |
|
Pb6 |
1- Off 2- Green 3- Green 4- Off |
- |
Reserved |
Reserved |
|
Pb7 |
1- Off 2- Blink 3- Blink 4- Blink |
|
ACPI S0, hand off to BIOS control |
System on. BIOS not execution. This is the transition state to POST states. |
|
Pb8 |
|
1- Green 2- Off 3- Off 4- Off |
- |
Reserved |
Reserved |
Pb9 |
1- Blink 2- Off 3- Off 4- Blink |
|
Non-System board Regulator Failure |
A power failure has been detected on a plug-in component such as VRM, Video Riser, or Memory Riser. |
|
Pb10 |
1- Blink 2- Off 3- Blink 4- Off |
PSU Failure |
PSU may be bad or PSU cable may be crimped creating a short on a main power rail. (PS_ON asserted, PS_PWRGOOD not asserted) |
||
Pb11 |
1- Blink 2- Off 3- Blink 4- Blink |
|
PSU Cable Failure |
All PSU cables may not be properly connected to system board. (PS_ON asserted, missing a main power rail) |
|
Pb12 |
1- Blink 2- Blink 3- Off 4- Off |
|
System board Regulator Failure |
A power failure has been detected in one of the onboard system board regulators. This could be caused by a failed system board component or by a plug-in device creating a short on a regulated power rail. (PS_ON asserted, PS_PWRGOOD asserted, SYS_PWRGOOD de-asserted) |
|
Pb13 |
1- Blink 2- Blink 3- Off 4- Blink |
|
Mismatch |
Hardware detected a population incompatibility with a critical system component such as CPU, VRM, PSU, or MEMORY RISER. |
|
Pb14 |
1- Green 2- Green 3- Green 4- Off |
- |
Reserved |
Reserved |
|
Pb15 |
1- Green 2- Green 3- Green 4- Green |
- |
Reserved |
Reserved |
All POST codes except S0 are accompanied by a Solid Green Power LED state. If the power LED is not green please see the "Pre-POST Diagnostic LED Patterns" table.
State |
LED pattern ( 1 2 3 4 ) |
LED Description |
State Name |
State assignment |
State description |
S0a |
|
1- Off 2- Off 3- Off 4- Off |
OFF |
OFF |
Power LED Off. No power is supplied to the system. |
S0e |
|
1- Off 2- Off 3- Off 4- Off |
ON |
Normal Operation, ACPI S0 |
Power LED Solid Green. System has successfully booted and is operating normally. |
S1 |
|
1- Off 2- Off 3- Off 4- Solid |
RCM |
System is in Recovery Mode |
BIOS checksum failure was detected and the system is now in recovery mode. |
S2 |
|
1- Off 2- Off 3- Solid 4- Off |
CPU |
CPU |
CPU configuration activity is in progress or a CPU failure was detected. |
S3 |
1- Off 2- Off 3- Solid 4- Solid |
MEM |
Memory |
Memory subsystem configuration activity is in progress. Appropriate memory modules were detected but a memory failure has occurred. |
|
S4 |
|
1- Off 2- Solid 3- Off 4- Off |
PCI |
PCI device |
PCI device configuration activity is in progress or PCI device failure was detected. |
S5 |
|
1- Off 2- Solid 3- Off 4- Solid |
VID |
Video Card |
Video subsystem configuration activity in progress or video subsystem failure. |
S6 |
|
1- Off 2- Solid 3- Solid 4- Off |
STO |
Storage |
Storage device configuration in progress or storage subsystem failure. |
S7 |
|
1- Off 2- Solid 3- Solid 4- Solid |
USB |
USB |
USB subsystem configuration activity in progress or USB subsystem failure. |
S8 |
|
1- Solid 2- Off 3- Off 4- Off |
MEM |
Memory |
Memory subsystem configuration activity is in progress. No memory modules were detected. |
S9 |
|
1- Solid 2- Off 3- Off 4- Solid |
MBF |
System board |
Fatal system board failure detected. |
S10 |
|
1- Solid 2- Off 3- Solid 4- Off |
MEM |
Memory |
Memory subsystem configuration activity is in progress. Memory modules have been detected but appear to be incompatible or in an invalid configuration. |
S11 |
|
1- Solid 2- Off 3- Solid 4- Solid |
PRV |
Other pre-video activity |
Indicates routine system activity preceding video initialization. |
S12 |
|
1- Solid 2- Solid 3- Off 4- Off |
CFG |
Resource configuration |
System resource configuration in progress. |
S13 |
|
1- Solid 2- Solid 3- Off 4- Solid |
|
Reserved |
Reserved for future use. This pattern is being considered to indicate the Visual Off state on the Dimension systems. |
S14 |
|
1- Solid 2- Solid 3- Solid 4- Off |
POV |
Other post-video activity |
Indicates routine system activity subsequent to video initialization. |
S15 |
|
1- Solid 2- Solid 3- Solid 4- Solid |
STD |
Boot hand off |
Indicates End of POST process. LEDs are normally in this state briefly as POST completes. Once the hand-off to the OS is done, the LEDs turn off and transition to S0e state. |
When errors occur during a boot routine that cannot be reported on the monitor, the computer may emit a beep code that identifies the problem. The beep code is a pattern of sounds: for example, one beep, followed by a second beep, and then a burst of three beeps (code 1-1-3) means that the computer was unable to read the data in nonvolatile random-access memory (NVRAM). If the system loses power and beeps constantly when you turn it back on, the BIOS is probably corrupted.
System Beep Codes |
|||
Beep Code |
Description |
Beep Code |
Description |
1-1-2 |
CPU register test in progress |
2-4-3 |
1st 64 K RAM chip or data line failure - bit E |
1-1-3 |
CMOS read/write test in progress or failure |
2-4-4 |
1st 64 K RAM chip or data line failure - bit F |
1-1-4 |
BIOS ROM checksum in progress or failure |
3-1-1 |
Secondary DMA register test in progress or failure |
1-2-1 |
Timer Test in progress or failure |
3-1-2 |
Primary DMA register test in progress or failure |
1-2-2 |
DMA initialization in progress or failure |
3-1-3 |
Primary IMR test in progress or failure |
1-2-3 |
DMA page register read/write test in progress or failure |
3-1-4 |
Secondary IMR test in progress or failure |
1-3-1 |
RAM refresh verification in progress or failure |
3-2-2 |
Interrupt vector loading in progress |
1-3-2 |
1st 64 K RAM test in progress or failure |
3-2-4 |
Keyboard controller test in progress or failure |
1-3-3 |
1st 64 K RAM chip or data line failure (multi bit) |
3-3-1 |
CMOS power fail and checksum test in progress |
1-3-4 |
1st 64 K RAM odd/even logic failure |
3-3-2 |
CMOS Config info validation in progress |
1-4-1 |
1st 64 K RAM address line failure |
3-3-3 |
RTC/Keyboard controller not found |
1-4-2 |
1st 64 K RAM parity test in progress or failure |
3-3-4 |
Screen memory test in progress or failure |
1-4-3 |
Fail-safe timer test in progress |
3-4-1 |
Screen initialization test in progress or failure |
1-4-4 |
Software NMI port test in progress |
3-4-2 |
Screen retrace tests test in progress or failure |
2-1-1 |
1st 64 K RAM chip or data line failure - bit 0 |
3-4-3 |
Search for video ROM in progress |
2-1-2 |
1st 64 K RAM chip or data line failure - bit 1 |
4-2-1 |
Timer tick interrupt test in progress or failure |
2-1-3 |
1st 64 K RAM chip or data line failure - bit 2 |
4-2-2 |
Shutdown test in progress or failure |
2-1-4 |
1st 64 K RAM chip or data line failure - bit 3 |
4-2-3 |
Gate A20 failure |
2-2-1 |
1st 64 K RAM chip or data line failure - bit 4 |
4-2-4 |
Unexpected interrupt in Protected Mode |
2-2-2 |
1st 64 K RAM chip or data line failure - bit 5 |
4-3-1 |
RAM test in progress or failure above address 0FFFFh |
2-2-3 |
1st 64 K RAM chip or data line failure - bit 6 |
4-3-2 |
No memory in Bank 0 |
2-2-4 |
1st 64 K RAM chip or data line failure - bit 7 |
4-3-3 |
Interval Timer Channel 2 test in progress or failure |
2-3-1 |
1st 64 K RAM chip or data line failure - bit 8 |
4-3-4 |
Time-Of-Day Clock test in progress or failure |
2-3-2 |
1st 64 K RAM chip or data line failure - bit 9 |
4-4-1 |
Super I/O chip failure |
2-3-3 |
1st 64 K RAM chip or data line failure - bit A |
4-4-4 |
Cache test failure |
2-3-4 |
1st 64 K RAM chip or data line failure - bit B |
|
|
2-4-1 |
1st 64 K RAM chip or data line failure - bit C |
|
|
2-4-2 |
1st 64 K RAM chip or data line failure - bit D |
|
|
If you require further assistance, please contact Dell Technical Support. | ||
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