Dell 980 service manual Diagnostic Lights, Light Pattern Problem Description, Suggested Resolution

Page 23

4-4-3

4-4-4

Math-coprocessor test failure

Cache test failure

Diagnostic Lights

To help troubleshoot a problem, your computer has four lights labeled 1, 2, 3, and 4 on the bank panel. When the computer starts normally, the lights flash before turning off. If the computer malfunctions, the sequence of the lights help to identify the problem.

NOTE: After the computer completes POST, all four lights turn off before booting to the operating system.

Light Pattern

Problem

Description

 

Power

Diagnostic LEDs Button

LED

The computer is either turned off or not receiving power.

Suggested Resolution

Reseat the power cable in the power connector on the back of the computer and the electrical outlet.

Bypass power strips, power extension cables, and other power protection devices to verify that the computer turns on properly.

Ensure that any power strips being used are plugged into an electrical outlet and are turned on.

Ensure that the electrical outlet is working by testing it with another device, such as a lamp.

Ensure that the main power cable and front panel cable are securely connected to the system board.

Apossible system board failure has occurred.

Apossible system board, power supply, or peripheral failure has occurred.

Memory modules are detected, but a memory power failure has occurred.

A possible CPU or system board failure has occurred.

BIOS may be corrupt or missing.

Apossible system board

Unplug the computer. Allow one minute for the power to drain. Plug the computer into a working electrical outlet and press the power button.

Power off computer, leaving the computer plugged in. Press and hold the power supply test button on the rear of the power supply unit. If the LED next to the switch illuminates, the problem may be with your system board.

If the LED next to the switch does not illuminate, disconnect all internal and external peripherals, and press and hold the power supply test button. If it illuminates, there could be a problem with a peripheral.

If the LED still does not illuminate, remove the PSU connections from the system board, then press and hold the power supply button. If it illuminates, there could be a problem with the system board.

If the LED still does not illuminate, the problem is probably with the power supply.

If two or more memory modules are installed, remove the modules, then reinstall one module and restart the computer. If the computer starts normally, continue to install additional memory modules (one at a time) until you have identified a faulty module or reinstalled all modules without error. If only one memory module is installed, try moving it to a different DIMM connector and restart the computer.

If available, install verified working memory of the same type into your computer.

Replace the CPU with a known good CPU. If the computer still fails to boot, inspect the CPU socket for damage.

The computer hardware is operating normally but the BIOS may be corrupt or missing.

Remove all peripheral cards from the PCI and PCI-E slots and restart the computer. If the computer boots, add the peripheral cards back one by

Image 23
Contents Rev. A00 Before Working Inside Your Computer Working on Your ComputerWindows Vista Turning Off Your ComputerAfter Working Inside Your Computer WindowsVideo Technical SpecificationsProcessor MemoryExpansion Bus AudioNetwork System InformationDrives External ConnectorsControls and Lights System Board ConnectorsPower Environmental PhysicalBack to Contents Removing and Replacing Parts System Board Layout Page System Setup EPP Admin Password Min Deactivate default DNS Dell Diagnostics DiagnosticsTab Function Power Button Light CodesPower LightDescription State Off Option FunctionCode Cause Beep CodesBlinking Amber Solid Amber Green No time tick Suggested Resolution Diagnostic LightsLight Pattern Problem Description Page Back to Contents Removing the Cover CoverReplacing the Cover Cover Replacing the Cover Removing the Front Panel Front PanelReplacing the Front Panel Removing the Optical Drive Optical DrivePage Replacing the Optical Drive Removing the Hard Drive Hard DrivePage Page Page Replacing the Hard Drive Removing Expansion Cards Expansion CardsPage Replacing Expansion Cards Removing the Wireless Module Wireless ModulePage Page Page Replacing the Wireless Module Removing the Fan FanPage Replacing the Fan Removing the Heat Sink and Processor Heat Sink and ProcessorPage Page Replacing the Heat Sink and Processor Removing the Memory Modules MemoryReplacing the Memory Modules Removing the Internal Speaker Internal SpeakerReplacing the Internal Speaker Removing the Front Thermal Sensor Front Thermal SensorReplacing the Front Thermal Sensor Removing the Power Supply Power SupplyPage Page Replacing the Power Supply Removing the I/O Panel PanelReplacing the I/O Panel Control Panel Release the cable Remove the screw Remove the control panel from the chassis Replacing the Control Panel Removing the Intrusion Switch Intrusion SwitchReplacing the Intrusion Switch Removing the Coin-Cell Battery Coin-Cell BatteryReplacing the Coin-Cell Battery Removing the System Board System BoardPage Replacing the System Board
Related manuals
Manual 51 pages 22.86 Kb