HP 1915, 1930, 1925 Solving Minor Problems, Solving Audio Problems, Solving CD/DVD Drive Problems

Maintenance & Service Guide

Presario 1900 Series

Models: 1900T, 1905, 1906, 1910, 1915, 1919, 1920,

1922, 1925, 1926, 1927, 1928, 1929, and 1930

Before You Begin	Specifications	Parts Catalog
Removal Sequence	Troubleshooting	Battery Operations
Product Description	Pin Assignments	Index

Troubleshooting

Solving Minor Problems

Some minor problems and possible solutions are outlined in the following tables. If the problem appears related to a software application, check the documentation provided with the software.

Solving Audio Problems

Some common audio problems and solutions are listed in the following table.

Solving Audio Problems

Problem

Computer does not beep after the Power-On Self-Test (POST).

Probable Cause	Solution(s)
This is typical; it indicates successful	No action is required.
completion of the Power-On Self-Test
(POST).

Solving Battery Pack and Battery Gauge Problems

Some common causes and solutions for battery pack problems are listed in the following table. The "Solving Power Problems" section in this chapter may also be applicable.

Solving Battery Pack and Battery Gauge Problems

Problem	Probable Cause
Computer won't turn on when battery	Battery pack is discharged.
pack is inserted and power cord is
unplugged.

Computer is beeping and battery LED	Battery charge is low.
icon is blinking.

Solution(s)

Connect the computer to an external power source and charge the battery pack.

Replace the battery pack with a fully charged battery pack.

Check the battery connectors on the system board to verify they are evenly spaced and that they are not bent or broken.

Immediately save any open file(s). Then do any one of the following:

●Connect the computer to an external power source to charge the battery pack.

●Turn off the computer or initiate Hibernation until you can find another power source or charge the battery pack.

Computer battery LED icon (front on	Volume is turned down too low.
the unit) blinks to indicate low battery
condition, but computer does not beep.
Battery LED icon doesn't light and	Battery pack is already charged.
battery pack won't fast charge.	Battery pack was exposed to
	temperature extremes.
	Battery pack is at end of its life.

You have to set the date and time every RTC battery is dead. time you turn on the computer.

Battery charge does not last as long as	Battery is being exposed to high
expected.	temperatures or extremely cold
	temperatures.

	Battery has partially self-discharged.
	Power management is disabled.
	An external device or PC Card is
	draining the battery.
Battery pack is warm to the touch after	Normal warming has occurred due to
charging.	charging.
Battery pack operating time is far less	Power management is turned off or
than the documented average	disabled.
operating time.	An external device or PC Card is
	draining the battery.
	Battery pack has partially self-
	discharged.

Battery pack is being exposed to high temperatures or extremely cold temperatures.

Adjust the volume.

No action is necessary.

Allow time for the battery pack to return to room temperature.

Replace battery pack. Replace the RTC battery.

Keep the battery pack within the recommended operating temperature range 50° F to 104° F (10° C to 40° C) or recommended storage range

-4° F to 86° F (-20° C to 30° C ). Recharge the battery pack.

Recharge the battery. Discharge the battery completely and then recharge it.

Set a power management level in Computer Setup.

Turn off or disconnect external devices when not using them.

No action is required.

Enable power management in Computer Setup and in Windows Power Properties.

Turn off or disconnect external devices when not using them.

Condition the battery pack by fully charging, fully discharging, then fully recharging it.

To maintain the charge, leave battery packs in the computer when it is connected to external power.

If the computer is disconnected from external power for more than two weeks, remove battery packs from the computer to reduce the discharge rate.

Keep the battery pack within the recommended temperature ranges. Operating: 50° F to 104° F

(10° C to 40° C) Storage: -4° F to 86° F (-20° C to 30° C )

Recharge the battery pack.

Solving CD/DVD Drive Problems

Some common causes and solutions for CD/DVD drive problems are listed in the following table.

Solving CD/DVD Drive Problems

Problem Probable Cause Solution(s)

CD/DVD drive cannot read a compact	Compact disc or digital versatile disc
disc or digital versatile disc.	is upside down or is improperly
	inserted in the CD/DVD drive.
	CD is CD Plus or Pregap/Track 0 type.

Open the CD/DVD loading tray, lay the compact disc or digital versatile disc in it (label side up), then close the tray.

Cannot read these type CDs in 24x. Remove the CD.

Solving Diskette and Diskette Drive Problems

Some common causes and solutions for diskette and diskette drive problems are listed in the following table.

Solving Diskette and Diskette Drive Problems

Problem	Probable Cause	Solution(s)
Diskette drive cannot write to a	Diskette is write-protected.	Disable the diskette's write-
diskette.		protect feature or use a
		diskette that is not write-
		protected.
	Computer is writing to	Check the drive letter in the
	the wrong drive.	path statement.
	Not enough space is left	Use another diskette.
	on the diskette.
	Drive error has occurred.	Run Computer Checkup from
		the Compaq Diagnostics
		diskette.
	Diskette is not formatted.	Format the diskette. At
		the system prompt, enter
		FORMAT A:
Diskette drive cannot read a	The wrong type of diskette is	Use the type of diskette
diskette.	being used.	required by the drive.
	Diskette has a bad sector.	Copy files to hard drive or
		another diskette. Reformat bad
		floppy.
	Drive error has occurred.	Run Computer Checkup from
		the Compaq Diagnostics
		diskette.
	Diskette is not	Format the diskette. At the
	formatted.	system prompt, enter
		FORMAT A:
Cannot boot from diskette.	Bootable diskette is not in	Put the bootable diskette in
	drive A.	drive A.
	Diskette Boot has incorrect	Run Computer Setup and set
	setting in Computer Setup.	diskette as first to boot.

Solving Display Problems

This section lists some common causes and solutions for computer display and external monitor problems.

You can perform a monitor self-test on an external VGA color or monochrome monitor by disconnecting the monitor from the computer. To do so, complete the following steps:

1.Turn off the monitor.

2.Turn off the computer.

3.Disconnect the monitor signal cable from the computer.

4.Turn on the monitor and allow it to warm up for one minute.

The display should be white. A narrow black border may also appear on the left and right sides of the display. Either of these displays indicates that the monitor is working properly.

Solving Display Problems

Problem	Probable Cause
Screen is dim.	Control for brightness (if
	applicable) is not set properly.

	Computer screen is in direct
	light.
Screen is blank.	Screen save was initiated by
	Power Management due to
	lack of user activity.
	Display has overheated.

Display is blank and the Suspend System is in Suspend mode. icon is flashing.

Internal display is blank and the Display function was switched screen on an external monitor to the external monitor. displays information.

Solution(s)

Adjust the Brightness of the display by using Fn + F7 (¯ ) or

Fn + F8 (- ).

Tilt display or move computer.

Press any key or touch the Touch Pad.

If computer is in direct sunlight, move it and allow it to cool off.

Press any key or touch the Touch Pad.

Use Fn + F2 to switch between LCD or CRT.

Internal display flashes or has garbled characters when computer is connected to external monitor.

The light tubes on the edge of the display panel do not light up at all and Power-On Self-Test (POST) completes when the unit is powered up.**

The light tubes on the edge of the display panel do not light up at all and Power-On Self-Test (POST) does not complete when the unit is powered up.**

Using 1024 × 768 or higher	Restart the computer.
resolution on external monitor
and have toggled back to
internal display, which
supports up to
800 × 600.
Improper backlight or display cable	Replace the display assembly.
connections
Defective inverter board.	Replace the display assembly.
Defective display cable.	Replace the display assembly.
Defective display panel.	Replace the display assembly.
Defective system board.	Replace the system board.
Defective system board.	Replace the system board.

Backlight (brightness) cannot be	Improper display cable connections.	1. Reseat the display cable to the
adjusted with Fn + F7 (¯ ) or		system board.
Fn + F8 (- ).***
		2. Replace the display assembly.
	Defective inverter board.	Replace the display assembly.
	Defective display cable.	Replace the display assembly.
	Defective system board.	Replace the system board.
	Defective inverter board.	Replace the display assembly.
	Defective display cable.	Replace the display assembly.
	Defective system board.	Replace the system board.

**This problem indicates that the backlight or its power circuitry has failed. Since you cannot observe the POST result on the display panel when the backlight is not functioning, connect the unit to an external monitor before powering the unit up. If an external monitor is not available, verify that POST completes by opening and closing the display, listening for the single or double beep, and watching for the LEDs turn on at the front of the computer.

This display panel has a continuous pattern	Improper display cable	Reseat the display cable to the following
across it (e.g., a "jailbars" pattern), has a	connections	until the problem is solved:
single color on it, or has garbled graphics
across the entire panel. This failure is for		1.	System board
patterns across the entire panel (not just on
one section).		2.	Display assembly

Defective display cable. Replace the display assembly.

Defective inverter board. Replace the display assembly.

Defective system board. Replace the system board.

To perform a "self-test" on an external VGA color monitor, complete the following steps: The screen should be

NOTE: white. A narrow black border may also appear on the left and right sides of the display. Either of these displays indicates that the monitor is working properly.

Solving Hard Drive Problems

Some common causes and solutions for hard drive problems are listed in the following table.

CAUTION: To prevent loss of information, always maintain an up-to-date backup of your hard drive at all times, in case of errors or failures.

	Solving Hard Drive Problems
Problem	Probable Cause
Reading hard drive takes an unusually	System entered Hibernation due to
long time after restarting the computer.	low battery condition and is now
	exiting from it.
Hard drive error occurs.	Hard drive has bad sectors or has
	failed.
Hard drive does not work.	Hard drive is not seated properly.

Solution(s)

Give the system time to restore the previously saved data to its exact state before Hibernation.

Run Computer Checkup.

Turn off and unplug the computer, remove the battery pack, and remove and then reinstall the hard drive.

Solving Hardware Installation Problems

Some common causes and solutions for hardware installation problems are listed in the following table.

Solving Hardware Installation Problems

Problem	Probable Cause	Solutions(s)
A new device is not recognized as Cable(s) of new external		Ensure that all cables are
part of the computer system.	device are loose or	properly and securely
	power cables are unplugged.	connected.
	Power switch of new external	Turn off the computer, turn on
	device is not turned on.	the external device, then turn
		on the computer to integrate
		the device with the computer
		system.
	Device is not seated properly.	Turn off the computer and
		reinsert the device.

Solving Keyboard/Numeric Keypad Problems

Some common causes and solutions for keyboard/numeric keypad problems are listed in the following table.

Solving Keyboard/Numeric Keypad Problems

Problem	Probable Cause	Solution(s)
Embedded numeric keypad on	Num Lock function is not	Press the Shift + NumLk
computer keyboard is disabled.	enabled.	keys to enable the Num Lock
		function and embedded
		numeric keypad. The Num
		Lock icon on the status panel
		turns on.
Embedded numeric keypad is	External numeric keypad is	Disconnect the external
disabled and Num Lock function is	connected to the computer.	numeric keypad from the
on.		computer.

Solving Memory Problems

Some common causes and solutions for memory problems are listed in the following table.

Solving Memory Problems

Problem	Probable Cause	Solution(s)
Memory count during Power-On Self- Optional memory expansion		Ensure that the optional
Test (POST) is incorrect.	card is installed incorrectly,	memory expansion card is
	is incompatible with	installed correctly.
	the computer, or is defective.

"Out of Memory" message is displayed on the screen or insufficient memory error occurs during operation.

System ran out of

memory for the application.

Too many TSR (terminate- and stay-resident) applications are running.

Check the application documentation for memory requirements.

Install additional memory.

Remove from memory any TSR applications that you do not need.

Solving Minor Problems (continued)