Initial User Contact | External Visual Inspection | Observing the Boot Routine | Internal Visual Inspection | Eliminating Resource Conflicts | Running the Diskette-Based Diagnostics | Getting Help
This chapter describes basic troubleshooting procedures that can help you diagnose a computer system problem. These procedures can often reveal the source of a problem or indicate the correct starting point for troubleshooting the system. A brief explanation of how to load and start the diskette-based diagnostics is located at the end of the chapter. Dell recommends that you perform these procedures in the order they are presented in this manual.
When you first contact a user who has a problem, ask the user to describe the problem and the conditions under which it occurs. A verbal description can often indicate the cause of a problem or indicate the appropriate troubleshooting procedure to use. After the user describes the problem, follow these steps:
Can the user duplicate the problem?
Yes. Proceed to step 3.
No. Proceed to the next section, "External Visual Inspection."
Is the problem a result of user error?
Yes. Instruct the user in the proper procedure, or direct him or her to the appropriate user documentation for the correct procedure.
No. Proceed to the next section, "External Visual Inspection."
The external visual inspection consists of a quick inspection of the exterior of the system unit, the monitor, the keyboard, any peripherals, and cables. While performing the visual inspection, make any necessary corrections. To perform the external visual inspection, follow these steps:
Does the inspection reveal any problems?
Yes. Refer to the appropriate procedure in Chapter 4, "Removing and Replacing Parts."
No. Proceed to the next section, "Observing the Boot Routine."
After you have performed an external visual inspection as described in the previous procedure, you should boot the system and, while the boot routine is running, observe the system for any indications of problems.
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NOTE: Most of the steps in this procedure require
observation of system functions and indications, some of
which can occur simultaneously. It may be necessary to
reboot the system several times in order to complete all
of these steps. |
To observe problem indications during the boot routine, follow these steps:
Does the fan run normally?
Yes. Proceed to step 3.
No. Troubleshoot the system power supply.
Do these indicators flash on and off within approximately 10 seconds after the boot routine starts?
Yes. Proceed to step 4.
No. Troubleshoot the system power supply. If the troubleshooting procedure indicates that the system power supply is operational, troubleshoot the memory.
- Diskette-drive and hard-disk drive access indicator activity - These indicators light up in response to data being transferred to or from the drives. If either of these indicators fails to light up during the boot routine, troubleshoot the diskette drive or hard-disk drive subsystem, as appropriate.
- Beep codes - A beep code is a series of beeps that indicates an error condition. If the system emits a beep code, refer to Table 3-1.
NOTE: The system beeps once during the boot routine. This single beep is normal and is not a beep code.
- System error messages - These messages can indicate problems or provide status information. If a system error message is displayed, refer to Table 3-2.
Does the Diagnostics Menu appear?
Yes. See "Running the Diskette-Based Diagnostics."
No. Proceed to step 6.
Does the Diagnostics Menu appear?
Yes. See "Running the Diskette-Based Diagnostics."
No. Proceed to the next section, "Internal Visual Inspection."
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CAUTION: Before you proceed with the internal visual inspection described in this section, ensure that the user has saved all open files and exited all open application programs if possible. |
A simple visual inspection of a system unit's interior hardware can often lead to the source of a problem, such as a loose expansion card, cable connector, or mounting screw. When you perform the visual inspection, refer to "System Features" in Chapter 1 to locate parts referenced in the inspection procedure.
To perform the internal visual inspection, follow these steps:
- Turn off the system, including any attached peripherals, and disconnect all the AC power cables from their power sources.
- Remove the system unit cover.
- Verify that all chips, DIMMs, and expansion cards are fully seated in their sockets or connectors.
To ensure that the chips are fully seated in their sockets, press firmly on the top of each chip. To reseat the microprocessor, remove it from its socket and reinstall it as described in "Microprocessor/Heat Sink Assembly" in Chapter 4.
To reseat a DIMM, remove it from its socket and reinstall it as described in "DIMMs" in Chapter 4.
If you need to reseat an expansion card, use a 1/4-inch nut driver to remove the screw that secures the card-mounting bracket. Grasp the card by its top corners, and carefully pull it out of its connector. Reinsert the card in its connector, and carefully push it in until it is fully seated. Then reinstall the card-mounting bracket's retaining screw.
- Verify that all configuration jumpers are set correctly. For information about these jumpers, see "Configuration Jumpers" in Chapter 1.
- Check all cable connectors inside the system unit to verify that they are firmly attached to their appropriate connectors.
- Reinstall the system unit cover.
- Reconnect the system unit and any attached peripherals to their power sources, and turn them on.
Does the problem appear to be resolved?
Yes. No further steps are necessary.
No. Proceed to the next section, "Eliminating Resource Conflicts."
Devices within or connected to the system unit may require
dedicated memory spaces, interrupt levels, or DMA channels, all
of which must be allocated during installation of the devices.
Because devices may be installed at different times, it is
possible the same resource is assigned to two or more devices.
Resource conflicts can result in disorderly or erratic system
operation or failure of the system to operate at all. If you
suspect that resource conflicts might exist, check the system and
reassign the resources as necessary.
The diskette-based diagnostics (included with the system)
contains tests that aid in troubleshooting all major components
of the computer system.
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CAUTION: To prevent damage to the original diagnostics diskette, always use a backup copy of the diagnostics diskette when servicing a user's system. Dell recommends that users make several copies of this diskette to ensure that one is always available. |
To start the diagnostics, turn off the system unit, insert a diagnostics diskette into drive A, and then turn on the system unit.
Starting the diagnostics causes the DellŪ logo screen to appear on the monitor screen, followed by a message indicating that the diagnostics is loading. Before the diagnostics loads, a program tests the portion of main memory (RAM) required for loading the diagnostics. If a main memory error is detected, a message is displayed that specifies which DIMM has failed.
If no errors are found in main memory, the diagnostics loads and the Diagnostics Menu appears. This menu lets you choose the following options or exit to the MS-DOSŪ prompt:
Runs
selected tests from all test groups to quickly locate a
failure or to indicate where further testing is needed to
isolate a failureTests a
particular area or subsystem If none of the troubleshooting procedures in this chapter or the tests in the diskette-based diagnostics reveals the source of the problem or leads to the proper troubleshooting steps for determining the source of the problem, call Dell for technical assistance. For instructions, see the chapter titled "Getting Help" in the Diagnostics and Troubleshooting Guide.