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Precision T3500/T5500/T7500 Workstations Diagnostic Lights and Beep Codes

Summary: Descriptions for the diagnostic lights and beep codes on you Dell Precision T3500, T5500, and T7400 workstations.

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Article Content


Symptoms

Diagnostic and Status Lights

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:

  • No light — System is in the off state (S5, or mechanical (AC power not applied) OFF).
  • Solid Amber — System fault, but Power Supply is good—normal operating state (S0).
  • Blinking Amber — System fault error condition including Power Supply (only +5VSB working), Vreg failure, missing or bad CPU.
  • Blinking Green — System is in power saving states S1, S3 or S4. (Blink rate is 1Hz). No fault/error condition.
  • Solid Green — System is fully functional and is in S0 (ON) state.

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.

SLN288786_en_US__11390254184194.diag_leds

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.

Pre – POST Diagnostic LED Patterns

State

LED Pattern ( 1 2 3 4 )

LED Description

Power LED

State Assignment

State Description

Pb0a

SLN288786_en_US__21390254274789.Pb0

1- Off 2- Off 3- Off 4- Off

SLN288786_en_US__31390254370776.PowerLEDOff

System Unplugged

System is not plugged into AC, PSU is not plugged into system board, or control panel not connected to system board.

Pb0b

SLN288786_en_US__41390254406245.Pb0

1- Off 2- Off 3- Off 4- Off

SLN288786_en_US__51390254456027.PowerLEDGreen

ACPI S0; Normal Operation

System is on with no failures detected. This is actually a BIOS controlled state and is also S0e.

Pb0c

SLN288786_en_US__61390318750560.Pb0

1- Off 2- Off 3- Off 4- Off

SLN288786_en_US__71390318798686.PowerLEDBlinkGreen

ACPI S1

Windows Standby State.

Pb1

SLN288786_en_US__81390319388291.Pb0

1- Off 2- Off 3- Off 4- Off

SLN288786_en_US__91390319452683.PowerLEDOff

ACPI S4 or S5

Hibernate or Soft off. System plugged in, but either turned off or in Windows Hibernation State.

Pb2

SLN288786_en_US__101390319879894.Pb2

1- Off 2- Off 3- Solid 4- Off

-

Reserved

Reserved

Pb3

SLN288786_en_US__111390319932817.Pb3

1- Off 2- Off 3- Solid 4- Solid

SLN288786_en_US__121390319505840.PowerLEDBlinkGreen

ACPI S3

Suspend to RAM Windows Standby State.

Pb4

SLN288786_en_US__131390319996537.Pb4

1- Off 2- Green 3- Off 4- Off

-

Reserved

Reserved

Pb5

SLN288786_en_US__141390320068507.Pb5

1- Off 2- Green 3- Off 4- Green

-

Reserved

Reserved

Pb6

SLN288786_en_US__151390320106961.Pb6

1- Off 2- Green 3- Green 4- Off

-

Reserved

Reserved

Pb7

SLN288786_en_US__161390320151118.Pb7

1- Off 2- Blink 3- Blink 4- Blink

SLN288786_en_US__171390319572294.PowerLEDAmber

ACPI S0, hand off to BIOS control

System on. BIOS not execution. This is the transition state to POST states.

Pb8

SLN288786_en_US__181390320526781.Pb8

1- Green 2- Off 3- Off 4- Off

-

Reserved

Reserved

Pb9

SLN288786_en_US__191390320583204.Pb9

1- Blink 2- Off 3- Off 4- Blink

SLN288786_en_US__201390319626811.PowerLEDAmber

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

SLN288786_en_US__211390320625408.Pb10

1- Blink 2- Off 3- Blink 4- Off

SLN288786_en_US__221390319716125.PowerLEDBlinkAmber

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

SLN288786_en_US__231390320675956.Pb11

1- Blink 2- Off 3- Blink 4- Blink

SLN288786_en_US__241390319758438.PowerLEDAmber

PSU Cable Failure

All PSU cables may not be properly connected to system board. (PS_ON asserted, missing a main power rail)

Pb12

SLN288786_en_US__251390320719379.Pb12

1- Blink 2- Blink 3- Off 4- Off

SLN288786_en_US__261390319787470.PowerLEDAmber

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

SLN288786_en_US__271390320751754.Pb13

1- Blink 2- Blink 3- Off 4- Blink

SLN288786_en_US__281390319825549.PowerLEDOff

Mismatch

Hardware detected a population incompatibility with a critical system component such as CPU, VRM, PSU, or MEMORY RISER.

Pb14

SLN288786_en_US__291390320791396.Pb14

1- Green 2- Green 3- Green 4- Off

-

Reserved

Reserved

Pb15

SLN288786_en_US__301390320822599.Pb15

1- Green 2- Green 3- Green 4- Green

-

Reserved

Reserved

Cause


POST Diagnostic LED Patterns

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

SLN288786_en_US__311390320890866.S0

1- Off 2- Off 3- Off 4- Off

OFF

OFF

Power LED Off. No power is supplied to the system.

S0e

SLN288786_en_US__321390320923461.S0

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

SLN288786_en_US__331390321146449.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

SLN288786_en_US__341390321201091.S2

1- Off 2- Off 3- Solid 4- Off

CPU

CPU

CPU configuration activity is in progress or a CPU failure was detected.

S3

SLN288786_en_US__351390321236904.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

SLN288786_en_US__361390321279811.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

SLN288786_en_US__371390321349188.S5

1- Off 2- Solid 3- Off 4- Solid

VID

Video Card

Video subsystem configuration activity in progress or video subsystem failure.

S6

SLN288786_en_US__381390321423799.S6

1- Off 2- Solid 3- Solid 4- Off

STO

Storage

Storage device configuration in progress or storage subsystem failure.

S7

SLN288786_en_US__391390321455330.S7

1- Off 2- Solid 3- Solid 4- Solid

USB

USB

USB subsystem configuration activity in progress or USB subsystem failure.

S8

SLN288786_en_US__401390321483440.S8

1- Solid 2- Off 3- Off 4- Off

MEM

Memory

Memory subsystem configuration activity is in progress. No memory modules were detected.

S9

SLN288786_en_US__411390321516816.S9

1- Solid 2- Off 3- Off 4- Solid

MBF

System board

Fatal system board failure detected.

S10

SLN288786_en_US__421390321567786.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

SLN288786_en_US__431390321613130.S11

1- Solid 2- Off 3- Solid 4- Solid

PRV

Other pre-video activity

Indicates routine system activity preceding video initialization.

S12

SLN288786_en_US__441390321642959.S12

1- Solid 2- Solid 3- Off 4- Off

CFG

Resource configuration

System resource configuration in progress.

S13

SLN288786_en_US__451390321681538.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

SLN288786_en_US__461390321716257.S14

1- Solid 2- Solid 3- Solid 4- Off

POV

Other post-video activity

Indicates routine system activity subsequent to video initialization.

S15

SLN288786_en_US__471390321742164.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.


Diagnostic Beep Codes

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.
     

 

 

Resolution


Out of Warranty support Out of warranty? No problem. Browse to the Dell.com/support website and enter your Dell Service Tag and view our offers.

NOTE: Offers are only available for US, Canada, UK, France, Germany, and China personal computer customers. Server and Storage not applicable.

Article Properties


Affected Product

Precision T3500, Precision T5500, Precision T7500

Last Published Date

03 Jun 2021

Version

4

Article Type

Solution

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