This article provides information on the power and diagnostic LED configuration status for the Precision Workstation T3610, T5610, or T7610 systems.
The diagnostic LEDs are located on the front of the chassis and numbered 1, 2, 3, 4. The LEDs are located beneath the headphone and microphone jacks. These diagnostic LEDs are only active and visible during the Power On Self-Test (POST) process. Once the operating system starts to load, they turn off and are no longer visible.
The configuration of these LEDs along with the color state of the power button can help pinpoint a potential problem with the system. Each LED has three possible states: OFF, ON, or BLINKING. Use the chart below as a reference for the different LED patterns and the possible system issues they indicate.
Power LED state | Description |
Off |
Power is off, LED is blank. |
Blinking amber |
Initial state of LED at power up. Indicates system has power, but the POWER_GOOD signal is not yet active. If the Hard Drive LED is off, it is probable that the power supply needs to be replaced. If the Hard Drive LED is on, it is probable that an onboard regulator or VRM has failed. Look at the diagnostic LEDs for further information. |
Solid amber |
Second state of the LED at power up. Indicates the POWER_GOOD signal is active and it is probable that the power supply is fine. Look at the diagnostic LEDs for further information. |
Blinking white |
System is in a low power state, either S1 or S3. Look at the diagnostic LEDs to determine which state the system is in. |
Solid white |
System is in S0 state, the normal power state of a functioning machine. The BIOS will turn the LED to this state to indicate it has started fetching operation codes. |
LED pattern (1 2 3 4) |
LED description | Power LED | State description |
1- Off 2- Off 3- Off 4- Off |
System is not plugged into AC, PSU is not plugged into system board, or control panel not connected to system board. | ||
1- Off 2- Off 3- Off 4- Off |
System is on with no failures detected. This is actually a BIOS controlled state and is also S0e. | ||
1- Off 2- Off 3- Off 4- Off |
Windows Standby State. | ||
1- Off 2- Off 3- Off 4- Off |
Hibernate or Soft off. System plugged in, but either turned off or in Windows Hibernation State. | ||
1- Off 2- Off 3-Solid 4- Off |
- | Reserved | |
1- Off 2- Off 3- Solid 4- Solid |
Suspend to RAM Windows Standby State. | ||
1- Off 2- Solid 3- Off 4- Off |
- | Reserved | |
1- Off 2- Solid 3- Off 4- Solid |
- | Reserved | |
1- Off 2- Solid 3- Solid 4- Off |
- | Reserved | |
1- Off 2- Blink 3- Blink 4- Blink |
System on. BIOS not execution. This is the transition state to POST states. | ||
1- Solid 2- Off 3- Off 4- Off |
- | Reserved | |
1- Blink 2- Off 3- Off 4- Blink |
A power failure has been detected on a plug-in component such as VRM, Video Riser, or Memory Riser. | ||
1- Blink 2- Off 3- Blink 4- Off |
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) | ||
1- Blink 2- Off 3- Blink 4- Blink |
All PSU cables may not be properly connected to system board. (PS_ON asserted, missing a main power rail) | ||
1- Blink 2- Blink 3- Off 4- Off |
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) | ||
1- Blink 2- Blink 3- Off 4- Blink |
Hardware detected a population incompatibility with a critical system component such as CPU, VRM, PSU, or MEMORY RISER. | ||
1- Solid 2- Solid 3- Solid 4- Off |
- | Reserved | |
1- Solid 2- Solid 3- Solid 4- Solid |
- | Reserved |
LED pattern (1 2 3 4) |
LED description | State description |
1- Off 2- Off 3- Off 4- Off |
Power LED Off. No power is supplied to the system. | |
1- Off 2- Off 3- Off 4- Off |
Power LED Solid Green/Blue or White. System has successfully booted and is operating normally. | |
1- Off 2- Off 3- Off 4- Solid |
BIOS checksum failure was detected and the system is now in recovery mode. | |
1- Off 2- Off 3-Solid 4- Off |
CPU configuration activity is in progress or a CPU failure was detected. | |
1- Off 2- Off 3- Solid 4- Solid |
Memory subsystem configuration activity is in progress. Appropriate memory modules were detected but a memory failure has occurred. | |
1- Off 2- Solid 3- Off 4- Off |
PCI device configuration activity is in progress or PCI device failure was detected. | |
1- Off 2- Solid 3- Off 4- Solid |
Video subsystem configuration activity in progress or video subsystem failure. | |
1- Off 2- Solid 3- Solid 4- Off |
Storage device configuration in progress or storage subsystem failure. | |
1- Off 2- Solid 3- Solid 4- Solid |
USB subsystem configuration activity in progress or USB subsystem failure. | |
1- Solid 2- Off 3- Off 4- Off |
Memory subsystem configuration activity is in progress. No memory modules were detected. | |
1- Solid 2- Off 3- Off 4- Solid |
Fatal system board failure detected. | |
1- Solid 2- Off 3- Solid 4- Off |
Memory subsystem configuration activity is in progress. Memory modules have been detected but appear to be incompatible or in an invalid configuration. | |
1- Solid 2- Off 3- Solid 4- Solid |
Indicates routine system activity preceding video initialization. | |
1- Solid 2- Solid 3- Off 4- Off |
System resource configuration in progress. | |
1- Solid 2- Solid 3- Off 4- Solid |
Reserved for future use. | |
1- Solid 2- Solid 3- Solid 4- Off |
Indicates routine system activity subsequent to video initialization. | |
1- Solid 2- Solid 3- Solid 4- Solid |
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 a fully off state. |
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