Manuals

Chapter 2, "Basic Troubleshooting": Dell Dimension P133v, P166v, and P200v

Chapter 2, "Basic Troubleshooting": Dell™ Dimension™ P133v, P166v, and P200v

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.

Initial User Contact

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:

Ask the user to back up any data on the hard-disk drive if the system's condition permits. See "Maintaining the System" in the online System User's Guide for information about backing up data.
Ask the user to try to duplicate the problem by repeating the operations he or she was performing at the time the problem occurred.

Can the user duplicate the problem?

Yes. Proceed to step 3.
No. Proceed to the next section, "External Visual Inspection."

Observe the user to determine if he or she is making an error, such as typing an incorrect key combination or entering a command incorrectly.

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."

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:

Turn off the system unit, the monitor, and all peripherals.
Verify that all power cables are properly connected to the system unit, the monitor and peripherals, and their power sources.
Verify that the keyboard and mouse interface cables are firmly attached to the proper connectors on the back of the system unit.
For a PS/2-compatible mouse, the keyboard and mouse interface cable connectors are identical except for their labels. Verify that the keyboard and mouse interface cable connectors are firmly attached to the proper connectors on the back of the system unit. To identify the proper connectors, see Figure 1-6.

For a serial mouse, the mouse interface cable must be firmly attached to the serial port connector, and its captive screws must be secure enough to ensure a firm connection.
Verify that any devices attached to the serial and parallel port connectors are properly connected.

Each of the serial and parallel interface cable connectors must be firmly attached to an appropriate connector on the back of the system unit as well as to the interface connector on the device. The captive screws that secure these connectors at each end of the interface cable must be secure enough to ensure a firm connection.
Verify that the video interface cable connector is firmly attached to the video connector and to the connector on the back of the monitor.

For proper connection of the video interface cable, see the documentation for the monitor.
Inspect all external monitor controls for any obvious damage or improper settings.

For proper settings of the monitor controls, see the documentation for the monitor.
Inspect the keyboard to ensure that no keys are sticking.

If one or more keys are sticking, it may be necessary to replace the keyboard.
Inspect the exterior of the system unit, including all controls, indicators, and user-accessible data storage devices, for any signs of physical damage.

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."

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.

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:

Insert the diagnostics diskette into drive A. Turn on all peripherals and the system unit. If the system unit is already on, press the reset button or <Ctrl><Alt><Del> to reboot the system.
Check the power supply fan.

Does the fan run normally?

Yes. Proceed to step 3.
No. Troubleshoot the system power supply.

Watch the Num Lock, Caps Lock, and Scroll Lock indicators on the upper-right corner of the keyboard. After all three indicators flash momentarily, the Num Lock indicator should light up and remain on.

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.

During the boot routine, observe the system unit for any of the following:

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.

Observe the monitor screen for the Diagnostics Menu.

Does the Diagnostics Menu appear?

Yes. See "Running the Diskette-Based Diagnostics."
No. Proceed to step 6.

Insert another copy of the diagnostics diskette into the diskette drive, and reboot the system.

Does the Diagnostics Menu appear?

Yes. See "Running the Diskette-Based Diagnostics."
No. Proceed to the next section, "Internal Visual Inspection."

Internal Visual Inspection

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.

NOTE: For your safety and protection of the system, observe the guidelines listed in "Precautionary Measures" in Chapter 4.

Verify that all chips, DIMMs, and expansion cards are fully seated in their sockets or connectors.

WARNING: The microprocessor can get extremely hot. Be sure the chip has had sufficient time to cool before you touch it.

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."

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.

Running the Diskette-Based Diagnostics

The diskette-based diagnostics (included with the system) contains tests that aid in troubleshooting all major components of the computer system.

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 Dell� 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-DOS� prompt:

Run Quick Tests -Runs selected tests from all test groups to quickly locate a failure or to indicate where further testing is needed to isolate a failure
Run All Tests - Runs all tests for a thorough check of the system
Run Specific Tests -Tests a particular area or subsystem

Getting Help

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.