Solving Minor Problems; Solving Audio Problems; Solving Hard Drive Problems - Compaq PRESARIO Presario 1255 Maintenance And Service Manual

Models: 1255, 1256, 1260, 1262, 1266, 1267, 1272, 1273, 1274, and 1275
Before You Begin
Removal Sequence
Product Description

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.
The following problems and possible solutions are addressed:
Audio Problems
Battery Pack and Battery Gauge Problems
CD Drive Problems
Diskette and Diskette Drive Problems
Display Problems
Hard Drive Problems
Hardware Installation Problems
Keyboard/Numeric Keypad Problems
Memory Problems

Solving Audio Problems

Some common audio problems and solutions are listed in the following table.
Problem
Computer does not beep after 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.
Problem
Computer won't turn on when battery
pack is inserted and power cord is
unplugged.
Computer is beeping and battery LED
icon is blinking.
Computer battery LED icon (front on
the unit) blinks to indicate low battery
condition, but computer does not beep.
Battery LED icon doesn't light and
battery pack won't fast charge.
You have to set the date and time every
time you turn on the computer.
Battery charge does not last as long as
expected.
Battery pack is warm to the touch after
charging.
Battery pack operating time is far less
than the documented average operating
time.
Solving CD Drive Problems
Some common causes and solutions for CD drive problems are listed in the following table.
Problem
CD drive cannot read a compact disc.
Solving Diskette and Diskette Drive Problems
Some common causes and solutions for diskette and diskette drive problems are listed in the
following table.
Problem
Diskette drive cannot write to a
diskette.
Diskette drive cannot read a
diskette.
Cannot boot from diskette.
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.
Problem
Screen is dim.
Screen is blank.
Display is blank and the Power icon
is flashing, or the Suspend icon is
present.
Internal display is blank and the
screen on an external monitor
displays information.
Internal display flashes or has
garbled characters when computer is
connected to external monitor.
The light tube-s 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.**
Backlight (brightness) cannot be adjusted with
Fn + F7 or Fn + F8.
Contrast cannot be adjusted with
Fn + F5 or Fn + F6.
** 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 to turn on at the front of the computer.
Problem
This display panel has a continuous pattern
across it (e.g., a "jailbars" pattern), has a
single color on it, or has garbled graphics
across the entire panel. This failure is for
patterns across the entire panel
(not just on one section).
Ghost bars extending from graphics on the
display.
A single line, a small group of lines, or a block
appears on the display panel. This failure
occurs in only a section of the display panel.
To perform a "self-test" on an external VGA color or monochrome monitor, complete the following steps: The
NOTE: screen 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 Hard Drive Problems

Some common causes and solutions for hard drive problems are listed in the following table.
CAUTION:
times, in case of errors or failures.
Problem
Reading hard drive takes an unusually
long time after restarting the computer.
Hard drive error occurs.
Hard drive does not work.
Solving Hardware Installation Problems
Some common causes and solutions for hardware installation problems are listed in the following
table.
Problem
A new device is not recognized as
part of the computer system.
Solving Keyboard/Numeric Keypad Problems
Some common causes and solutions for keyboard/numeric keypad problems are listed in the
following table.
Problem
Embedded numeric keypad on
computer keyboard is disabled.
Embedded numeric keypad is
disabled and Num Lock function is
on.
Solving Memory Problems
Some common causes and solutions for memory problems are listed in the following table.
Problem
Memory count during Power-On Self-
Test (POST) is incorrect.
"Out of Memory" message is
displayed on the screen or
insufficient memory error occurs
during operation.
Solving Minor Problems (continued)
or return to the Troubleshooting
Presario 1200 Series
Solving Audio Problems
Probable Cause
This is typical; it indicates successful
completion of the Power-On Self-Test
(POST).
Solving Battery Pack and Battery Gauge Problems
Probable Cause
Battery pack is discharged.
Battery charge is low.
Volume is turned down too low.
Battery pack is already charged.
Battery pack was exposed to
temperature extremes.
Battery pack is at end of its life.
RTC battery is dead.
Battery is being exposed to high
temperatures or extremely cold
temperatures.
Battery has partially self-discharged.
Power management is disabled.
An external device or PC Card is
draining the battery.
Normal warming has occurred due to
charging.
Power management is turned off or
disabled.
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.
Solving CD Drive Problems
Probable Cause
Compact disc is upside down or is
improperly inserted in the CD drive.
CD is CD Plus or Pregap/Track 0 type. Cannot read these type CDs in 24x.
Solving Diskette and Diskette Drive Problems
Probable Cause
Diskette is write-protected.
Computer is writing to
the wrong drive.
Not enough space is left
on the diskette.
Drive error has occurred.
Diskette is not formatted.
The wrong type of diskette is
being used.
Diskette has a bad sector.
Drive error has occurred.
Diskette is not formatted.
Bootable diskette is not in
drive A.
Diskette Boot has incorrect
setting in Computer Setup.
Solving Display Problems
Probable Cause
Control for brightness or
contrast (if applicable) is not
set properly.
Computer screen is in direct
light.
Screen save was initiated by
Power Management due to
lack of user activity.
Display has overheated.
System is in Suspend mode. Press any key or touch the
Display function was
switched to the external
monitor.
Using 1024 × 768 or higher
resolution on external
monitor and have toggled
back to internal display,
which supports up to 800 ×
600.
Improper backlight or display cable
connections
Defective inverter board.
Defective display cable.
Defective display panel.
Defective system board.
Defective system board.
Improper display cable connections. 1. Reseat the display cable to the
Defective inverter board.
Defective display cable.
Defective system board.
System may have a TFT display
(which is always at maximum
contrast)
Improper display-cable connections. 1. Reseat the display cable to the
Defective inverter board.
Defective display cable.
Defective system board.
Probable Cause
Improper display cable
connections
Defective display cable.
Defective inverter board.
Defective system board.
Common characteristic of STN
displays.
Defective display panel.
To prevent loss of information, always maintain an up-to-date backup of your hard drive at all
Solving Hard Drive Problems
Probable Cause
System entered Hibernation due to
low battery condition and is now
exiting from it.
Hard drive has bad sectors or has
failed.
Hard drive is not seated properly.
Solving Hardware Installation Problems
Probable Cause
Cable(s) of new external
device are loose, or
power cables are unplugged.
Power switch of new external
device is not turned on.
Device is not seated properly. Turn off the computer and
Solving Keyboard/Numeric Keypad Problems
Probable Cause
Num Lock function is not
enabled.
External numeric keypad is
connected to the computer.
Solving Memory Problems
Probable Cause
Optional memory expansion
card is installed incorrectly,
is incompatible with
the computer, or is defective.
System ran out of
memory for the application.
Too many TSR (terminate-
and stay-resident)
applications are running.
index page.
Specifications
Troubleshooting
Pin Assignments
Parts Catalog
Battery Operations
Index
Solution(s)
No action is required.
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 that they are
evenly spaced and 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.
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.
Solution(s)
Open the CD loading tray, lay the
compact disc in it (label side up), then
close the tray.
Remove the CD.
Solution(s)
Disable the diskette's write-
protect feature or use a
diskette that is not write-
protected.
Check the drive letter in the
path statement.
Use another diskette.
Run Computer Checkup from
the Compaq Diagnostics
diskette.
Format the diskette. At
the system prompt, enter
FORMAT A:
Use the type of diskette
required by the drive.
Copy files to hard drive or
another diskette. Reformat bad
floppy.
Run Computer Checkup from
the Compaq Diagnostics
diskette.
Format the diskette. At the
system prompt, enter
FORMAT A:
Put the bootable diskette in
drive A.
Run Computer Setup and set
diskette as first to boot.
Solution(s)
Adjust the Brightness of the
display by using Fn + F7 or
Fn + F8.
Adjust the Contrast of the
display by using Fn + F5 or
Fn + F6.
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.
Touch Pad.
Use Fn + F3 to switch
between LCD or CRT.
Restart the computer.
Replace the display assembly.
Replace the display assembly.
Replace the display assembly.
Replace the display assembly.
Replace the system board.
Replace the system board.
system board.
2. Replace the display assembly.
Replace the display assembly.
Replace the display assembly.
Replace the system board.
No adjustment is possible.
system board.
2. Replace the display assembly.
Replace the display assembly.
Replace the display assembly.
Replace the system board.
Solution(s)
Reseat the display cable to the following
until the problem is solved:
1. System board
2. Display assembly
Replace the display assembly.
Replace the display assembly.
Replace the system board.
1. Change the background colors.
2. Adjust the Contrast of the display by
using Fn + F5 or Fn + F6.
Replace the display assembly.
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.
Solutions(s)
Ensure that all cables are
properly and securely
connected.
Turn off the computer, turn on
the external device, then turn
on the computer to integrate
the device with the computer
system.
reinsert the device.
Solution(s)
Press the Shift+NumLk keys
to enable the Num Lock
function and embedded
numeric keypad. The Num
Lock icon on the status panel
turns on.
Disconnect the external
numeric keypad from the
computer.
Solution(s)
Ensure that the optional
memory expansion card is
installed correctly.
Check the application
documentation for memory
requirements.
Install additional memory.
Remove from memory any
TSR applications that you do
not need.