The information in this guide is subject to change without notice.
Compaq Computer Corporation shall not be liable for technical or editorial
errors or omissions contained herein; nor for incidental or consequential
damages resulting from the furnishing, performance, or use of this material.
This guide contains information protected by copyright.No part of this
guide may be photocopied or reproduced in any form without prior written
consent from Compaq Computer Corporation.
1986, 1990 Compaq Computer Corporation.
All rights reserved.Printed in the USA.
COMPAQ, DESKPRO, SYSTEMPRO, FASTART, Registered United States Patent and
Trademark Office.
The software described in this guide is furnished under a license agreement
or nondisclosure agreement.The software may be used or copied only in
accordance with the terms of the agreement.
Product names mentioned herein are for identification purposes only and may
be trademarks and/or registered trademarks of their respective companies.
COMPAQ PORTABLE II PERSONAL COMPUTER
MAINTENANCE AND SERVICE GUIDE
Second Edition (December 1990)
First Edition (February 1986)
Manual Assy No. 101206-002
Text PN 104208-002
Binder PN 104207-001
Preface
This publication is intended as a reference for technicians trained to repair
the COMPAQ PORTABLE II Personal Computer.
Summary of Text
This guide contains the following eight chapters:
Chapter 1, "Operating and Performance Specifications," provides physical,
environmental, and performance specifications for the COMPAQ PORTABLE II
Personal Computer.
Chapter 2, "Power On Self Test," describes the internal system diagnostic
programs that execute automatically when the system is turned on.It also
includes a quick reference for identifying and correcting problems that could
occur during the Power On Self Test procedure.
Chapters 3 and 4:Please see the SUPPORT SOFTWARE MAINTENANCE AND SERVICE
GUIDE for information on the SETUP and ADVANCED DIAGNOSTICS programs.
Chapter 5, "Error Messages and Codes," lists the Power On Self Test (POST) and
DIAGNOSTICS Error Codes and provides the course of action necessary to
resolve the problem.
Page 2
Chapter 6, "Illustrated Parts Catalog," provides an illustrated reference for
COMPAQ PORTABLE II Personal Computer spare parts.
Chapter 7, "Removal and Replacement Procedures," describes how to remove and
replace field replaceable subassemblies.
Chapter 8, "Jumper Settings, Switch Settings, and Adjustments," provides
detailed information for setting jumpers and switches and performing monitor
adjustments.
Tools and Supplies
The following tools and supplies are required to service the COMPAQ PORTABLE
II Personal Computer:
oTorx screwdrivers, sizes T-15 and T-10
oSlotted blade screwdriver, 1/4 inch
oNeedlenosed pliers
o25 pin printer loopback plug
o25 pin serial loopback plug
o9 pin serial loopback plug
oDIAGNOSTICS diskette
oFormatted diskette
Only trained technicians should attempt to repair this equipment.All
troubleshooting and repair procedures are detailed to allow
subassembly/module level repair only.
Because of the complexity of the individual boards and subassemblies, no one
should attempt to make repairs at the component level or make modifications
to any printed wiring board.Improper repairs may create a safety hazard.
Indications of component replacement or printed wiring board modifications
may void any warranty or exchange allowances.
The following support documentation is available for the COMPAQ PORTABLE II
Page 3
Personal Computer.
oOperations Guide
oMS-DOS VERSION 3 REFERENCE GUIDE
oTechnical Reference Guide
oHOW TO DO BUSINESS WITH COMPAQ SERVICE
oCOMPAQ SERVICE QUICK REFERENCE GUIDE
oCOMPAQ Service Advisories and Bulletins
oCOMPAQ QuickFind Support Reference Library
The computer is designed to be electrically grounded.To ensure proper
operation of the computer, plug the AC power cord only into a properly
grounded AC outlet.
CONNECTOR HOOD: RFI/EMI metal shield; AMP #7451 7X-X; or equivalent.
It is important that the chassis ground of any peripheral device be connected
to the computer chassis.An Alpha #1221 flat braid strap is sufficient.
This strap is not necessary if the shielded cable connects the two chassis.
Page 4
Chapter 1. Operating and Performance Specifications
Chapter 1.0 Introduction
This chapter contains operating and performance specifications for the COMPAQ
PORTABLE II Personal Computer.
Chapter 1.1 System Unit
Table 1-1.Electrical and Mechanical Specifications
==============================================================================
Dimensions:
Height7.5 in. (19.0 cm)
Depth13.9 in. (35.3 cm)
Width17.7 in. (45.0 cm)
-----------------------------------------------------------------------------WeightModel 1 23.6 lb (10.7 kg)
-----------------------------------------------------------------------------* These values are maximum values based on nominal operating conditions for
temperature, line voltage, frequency and altitude.Also, a minimum load on
l2 VDC must be maintained for proper power supply operation.
The Power On Self Test (POST) is a series of diagnostic tests performed
automatically when the system is turned on.These tests verify that the
computer system is operating properly.If a subassembly fails POST, an error
code appears on the screen.
To start POST, follow these steps.
1.Turn off the computer.
2.Disconnect the signal cables of any peripheral devices (printers, modems,
and so on) from the computer.
3.Remove the outer access casing to expose the system LED located on the
system board (see Chapter 7 for this procedure).
4.Install a loopback plug connector at each location from which a
peripheral signal cable was removed.
NOTE: To test your printer during the printer test or to log errors to a
printer, reconnect the printer now.
5.Verify that the AC power cable is connected to a usable, grounded, three
pronged AC power outlet.
6.Insert the DIAGNOSTICS diskette into drive A.
7.Turn on the computer.The system automatically runs POST.See
Section 2.2, "System Problem Isolation," for information on handling
system problems.
Chapter 2.2 System Problem Isolation
This section contains problem isolation procedures for identifying and
correcting system related problems.
To isolate system problems, perform the following steps:
1.Verify that the AC power switch is on.
2.Listen for the sound of the fan.Did you hear the fan?
YES: Proceed to step 3.
NO: Turn off the computer and check the condition of the AC power fuse.
Is the fuse good?
YES: Return the AC power fuse to its fuse holder and turn on the system.
Proceed to step 3.
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NO: Replace the AC power fuse (refer to Chapter 7 in this guide
for AC power fuse removal and replacement information).Repeat
steps 1 and 2.
3.Did you hear an audible beep or see an error code on the screen?
YES: See Chapter 5, "Error Messages and Codes" for information on how to
identify and correct either audible or error code related problems.
NO: Proceed to step 4.
4.Check the system LED on the system board.Is it lit?
YES: Proceed to step 5.If you did not hear the fan, replace it now.
NO: Replace the power supply subassembly chassis and repeat the problem
isolation procedures.
If the problem continues, replace the system board and repeat the problem
isolation procedures.
If the problem has not been corrected, test each controller or option board
by turning off the system, removing a board and turning the power back on.
If the LED is still not on, test each video and storage device by turning off
the system, disconnecting the device power cable and then turning on the
system.
When the system LED lights, power off the system and replace the defective
subassembly.
NOTE: For removal and replacement procedures, refer to Chapter 7.
5.Check the screen for a blinking cursor.Do you see a cursor on the
screen?
YES: Proceed to step 6.
NO: Listen for an audible tone (beep) from the system speaker.
If you hear one or two short beeps, POST is complete.The system now boots
the DIAGNOSTICS program.If the screen remains blank, adjust the brightness
knob.
If the display screen remains blank after adjusting the brightness knob, the
video display unit subsystem is not functioning properly.
oIf a color graphics or composite video monitor is available, connect
either device to the correct video outputs on the video display controller
board.Using the CTRL + ALT + < command, change the display mode to the
graphics mode.
If the first screen of the DIAGNOSTICS program appears on the external
monitor, replace the internal video display unit.
If the screen on the external monitor is blank, replace the video display
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controller board.
oIf a color graphics or composite video monitor is not available, replace
the video display controller board.
oIf a color graphics or composite video monitor is not available and
replacing the video display controller board does not solve the problem,
replace the internal video display unit.
If you do not hear a beep, replace the system board.If you hear any other
audible sounds, refer to Chapter 5 for more information on POST related error
messages.
6.Did the cursor disappear from the screen, replaced by the number of Kbytes
(shown in increments) on the display screen?
YES: This indicates the memory self test portion of POST.Proceed to
step 7.
NO: Replace the system board.Restart the system problem isolation
procedures.
7.Did the LEDs on the mass storage device flash, followed by one or two
short beeps?
YES: This indicates that POST and the SETUP utility have completed
successfully.The DIAGNOSTICS program should then boot and the
DIAGNOSTICS menu should appear on the display screen.
Refer to Chapter 4 for additional information on the COMPAQ
DIAGNOSTICS program.
NO: If the cursor reappears and remains on the screen, replace
the system board.
If one audible tone is heard and an error message appears, the SETUP
function was not completed on the system.Press the F1 key and
proceed to Chapter 3 in this guide for information on the SETUP
function.
Page 11
Chapter 3. Setup
Please consult the SUPPORT SOFTWARE MAINTENANCE AND SERVICE GUIDE for current
information on SETUP.
Page 12
Chapter 4. Diagnostic Procedures
Please consult the SUPPORT SOFTWARE MAINTENANCE AND SERVICE GUIDE for current
information on DIAGNOSTICS.
Page 13
Chapter 5. Error Messages and Codes
5.0 Introduction
This section contains Power On Self Test (POST) messages, DIAGNOSTIC error
codes, and memory error codes.The messages and codes are given in tables
that list the message or error code, a description of the error, the probable
cause of the error, and the action required to resolve the error condition.
Chapter 5.1 Power On Self Test Messages
An error message results if a problem is encountered during the Power On Self
Test.This utility runs automatically when the system is turned on.
Table 5-1 lists the message, audible (beep) message, probable cause, and the
recommended action.
Table 5-1.Power On Self Test Error Messages
==============================================================================
MessageBeepsProbable CauseRecommended Action
2.Replace multipurpose
fixed disk drive
controller board.
-----------------------------------------------------------------------------602 - DisketteNoneDiskette in DriveReplace diskette.
Boot Record ErrorA not bootable
-----------------------------------------------------------------------------1780 - Disk 0NoneFixed disk drive/Run DIAGNOSTICS.
Failureformat error
-----------------------------------------------------------------------------1782 - DiskNoneFixed disk drive/Run DIAGNOSTICS.
Controller failurecontroller error
-----------------------------------------------------------------------------1790 - Disk 0 ErrorNoneFixed disk driveRun SETUP and DIAGNOSTICS.
-----------------------------------------------------------------------------(RESUME = "F1" KEY)NoneAs indicatedPress F1 key to continue
==============================================================================
Chapter 5.2 Diagnostics Error Codes
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DIAGNOSTICS error codes occur if the system recognizes a problem while
running the DIAGNOSTICS program.These error codes help identify possible
defective subassemblies.
Table 5-2 through 5-12 list possible error codes, a description of the error
condition, and the action required to correct the condition.
In each case, the Recommended Action column lists steps necessary to correct
the problem.After completing each step, run the DIAGNOSTICS program to
verify that the error condition has been corrected.If the error code
reappears, perform the next step, then run the DIAGNOSTICS program.Continue
until the DIAGNOSTICS program no longer detects an error condition.
The error codes are in the form of AYY - XX or AAYY - XX, A or AA denotes the
test or action that failed.XX denotes a specific problem.For example,
error code 603 - 07 indicated that the diskette drive write/read/compare test
failed because of a fatal error while writing.
For assistance in the removal and replacement of a particular subassembly,
see Chapter 7, " Removal and Replacement Procedures."
Table 5-2.Processor Test Error Codes
==============================================================================
Error
CodesError DescriptionRecommended Action
-----------------------------------------------------------------------------101 - 01CPU test failedReplace the system board and
retest for error codes
101 - 01 through 101 - 94
-----------------------------------------------------------------------------102 - 01Numeric coprocessor initialThe following steps apply
status word incorrectto error codes 102 - 01
through 102 - 15:
102 - 02Numeric coprocessor initial
control word incorrect1.Replace the numeric
coprocessor and retest.
2.Replace the system
102 - 03Numeric coprocessor tag wordboard and retest.
-----------------------------------------------------------------------------694 - 00Pin 34 is not cut on 360 KB disketteSee Service Bulletin 25,
driveModification of 360 Kbyte
697 - 00Diskette type error
698 - 00Diskette drive speed not withinand retest.
limits2.Check the switch and
Diskette Drives.
1.Replace the diskette
jumper settings on the
multipurpose fixed disk
drive controller board
Page 24
or the multipurpose
controller board.
3.Replace the diskette
power and signal cables
and retest.
4.Replace the
multipurpose fixed disk
drive controller board
or multipurpose
controller board and
retest.
5.Replace the diskette
drive and retest
6.Replace the system
board and retest.
-----------------------------------------------------------------------------699 - 00Diskette drive/media ID errorRerun the SETUP program.
==============================================================================
Memory error codes result when the system detects a memory fault during the
Power On Self Test or diagnostic test.The Test programs attempt to isolate
the memory fault to a specific chip, then generate a memory error code that
identifies the defective memory chip.
In some cases, replacing the memory chip will not solve the problem because:
oThe system may not be able to accurately determine which chip or chips are
at fault.
oThe problem may be caused by to a failure in the memory support circuitry,
not the memory.
The memory error code points to a specific memory address.The physical
location of the memory address depends on the type of system, the number and
type of memory boards installed, and the type of memory device used
(64K x 1 Bit RAMs or 256K x 1 Bit RAMs).
Tables 5-14 through 5-17 identify which memory device to replace when the
system shows a memory error.Table 5-13 indicates the table to reference to
locate the defective chip.
NOTE: XX codes 0A to 0F represent the memory space for the video memory and
system ROMs.Errors in the video memory or system ROM space are not reported
in the XX000B YYZZ error message format.
==============================================================================
Page 33
Defective Memory Chip Isolation Map for System Boards using 64K RAMs and
256K RAMs
Memory error codes are in the format XX000B YYZZ.
XX is the memory segment of detected error.
000 is always equal to 000 (not used)
B Byte bank location (Low:B = 0, High:B = 1)
Page 34
YY Bit location of the low byte (B = 0)
ZZ Bit location of the high byte (B =1)
For example, for the Version 1 system board, memory error message
"02000 10010" specifies chip U47.
Use Tables 5-14 through 5-17 to locate the defective chip and determine the
required action.
NOTE: If XX or YY is not documented in the following tables, this may mean
that more than one area contributed to the error condition.If this is the
case, the system adds the values of the failed data bits and displays the sum
in the XX or YY location.
Figures 5-1 and 5-2 show the memory chip locations for the COMPAQ PORTABLE II
Personal Computer System Boards - Version 1 and 2.For information on
removing and replacing memory chips contained on the system board, refer to
Chapter 7 in this guide.
Table 5-14.Version 1 System Board using 64K RAMs (0 - 256 Kbytes)
==============================================================================
XX = 00 (Bank 0)
80U23U8Replace system board
==============================================================================
Defective Memory Chip Isolation Map for the 512/1536 Kbyte System Memory
Board Mapped into the 1 to 2.5 Megabyte Memory Space (256K x 1 Bit RAMs)
NOTE: This isolation map is valid for a system memory board that uses
256K x 1 bit RAMs.
Memory error codes are in the format XX000B YYZZ.
XX equals the 128 Kbyte memory segment where an error is detected.
000 is always equal to 000 (not used).
B Byte bank location (Low:B=0,High: B = 1)
YY Bit location of the low byte (B = 0)
ZZ Bit location of the high byte (B = 1)
Use the following table to locate the defective memory chip and the required
action.Figure 5-3 shows the memory chip locations for the COMPAQ
PORTABLE II Personal Computer System Memory Board (512/1536 Kbyte).For
information on removing and replacing memory chips contained on this board,
Page 38
refer to Chapter 7.
Table 5-18.Memory Locations/Required Action for 512/1536 Kbyte System Memory
Board Mapped to the 1 to 2.5 Megabyte Memory Space (256K x 1 Bit RAMs)
==============================================================================
XX = 10, 12, 14, 16 (Bank 2)
This section provides a spare parts reference for the COMPAQ PORTABLE II
Personal Computer.
Each table in this section contains the following information:
oItem - reference number keyed to an illustration.
oPart Number - to be used when ordering parts from Compaq Computer
Corporation.
oDescription - name of the particular part or parts kit.
NOTE: When several parts have the same part number, the parts are available
only as part of a kit.
Chapter 6.1 Compaq Portable II Personal Computer
Table 6-1.COMPAQ PORTABLE II Personal Computer
==============================================================================
ItemPart NumberDescription
** Part number no longer available.
==============================================================================
Chapter 6.2 Chassis
Table 6-2.COMPAQ PORTABLE II Personal Computer Chassis
==============================================================================
ItemPart NumberDescription
* Contained in the Miscellaneous Hardware Kit (Spare PN 104270-001 **).
See Table 6-7.
Page 42
** Part number no longer available.
==============================================================================
Chapter 6.3 Common Chassis
Table 6-3.COMPAQ PORTABLE II Personal Computer Common Chassis
==============================================================================
ItemPart NumberDescription
Contained in the Cable Kit, Spare PN 104191-001 **.See Table 6-6.
‰When replacing a flip door style diskette drive with a push button
style diskette drive, order a replacement drive bezel
(PN 104059-001 **) for a better fit.
**** Requires system ROM N3 or later for use with MS-DOS and ROM P.1 or later
for use with MS OS/2 Version 1.1.
Requires MS-DOS Version 3.31 Revision A if installed as Drive B, and
MS-DOS Version 3.31 Revision B if installed as Drive A.
**Part number no longer available.
==============================================================================
Page 45
Chapter 6.4 Mechanical Chassis
Table 6-4.COMPAQ PORTABLE II Personal Computer Mechanical Chassis
==============================================================================
ItemPart NumberDescription
* Contained in Miscellaneous Hardware Kit, Spare PN 104270-001 **.
** Part number no longer available.
==============================================================================
Chapter 6.5 Monitor
Page 46
Table 6-5.COMPAQ PORTABLE II Personal Computer Monitor
==============================================================================
ItemPart NumberDescription
Table 6-6.COMPAQ PORTABLE II Personal Computer Cable Kit (PN 104191-001
(No longer available))
==============================================================================
DescriptionQuantity
Power Grommet2
==============================================================================
Page 48
Chapter 7. Removal and Replacement Procedures
7.1 Preparation
Before beginning the procedures in this section, complete the following steps:
1.Turn off the computer.
2.Close the keyboard and secure it by sliding the latches to the LOCK
position (Figure 7-1) and folding the keyboard feet in place.
3.Disconnect any peripheral devices (printers, monitors, and so on) from the
computer.
4.Disconnect the AC power cord from the AC outlet and from the computer
(Figure 7-2).
Page 49
Chapter 7.2 AC Power Fuse
To remove the AC power fuse, complete the following steps:
1.Complete the preparation procedures (see Section 7.1).
2.Slide open the AC power compartment to expose the line filter ON/OFF
switch (Figure 7-3).
Page 50
3.Insert a flat bladed screwdriver along the bottom edge of the fuse box.
Lift outward with enough pressure to force the fuse box out of the casing
(Figure 7-4).
4.When the fuse box is removed, locate the spare fuse provided in the
holding area in the fuse box (Figure 7-5).Lift the fuse out and replace
it with the spare fuse.
5.Slide the fuse box back into place.Press the cover in until you feel it
snap into place.
NOTE: Use only a fuse with a 3 Ampere current rating.
Page 51
Chapter 7.3 Outer Access Casing
To remove the outer access casing from the computer, complete the following
steps:
1.Complete the preparation procedure (see Section 7.1).
2.Place the computer keyboard side down on a level work surface.Slide open
the AC power access panel and the peripheral connector access panels.
Using a Torx screwdriver, remove the mounting screws from the AC power
and peripheral connector access areas (Figures 7-6 and 7-7).
Page 52
3.Remove the outer access casing by grasping it close to the AC power and
peripheral connector access panels and sliding the cover towards you.
Slide it completely off the system chassis (Figure 7-8) and set it aside.
NOTE: The outer access casing is flexible and will bend as needed.
Page 53
To replace the outer access casing, reverse steps 2 and 3.
Chapter 7.4 Keyboard Assembly
To remove the keyboard assembly, complete the following steps:
1.Remove the cable tray access plate (see Section 7.13).
2.Disconnect the keyboard cable connector from the J116 socket connector on
the system board (Figure 7-9).
Page 54
3.Lower the rear portion of the computer so that it rests flatly against the
work surface (Figure 7-10).
4.Unlock the keyboard latches and gently slide the keyboard cable from
inside the computer system chassis (Figure 7-11).Remove the keyboard
from the computer system chassis.
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To replace the keyboard assembly, reverse steps 1 through 4.
Chapter 7.5 Front Bezel
To remove the front bezel, complete the following steps:
1.Remove the keyboard assembly (see Section 7.4).
2.Remove the brightness control knob by gently pulling it from the front
bezel (Figure 7-12).
Page 56
3.Lift the rear portion of the computer so that it rests firmly on the front
bezel (Figure 7-13).
4.Using a Torx screwdriver, remove the six screws that secure the front
bezel to the system chassis (Figure 7-14).
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5.Lower the system chassis and gently pull the front bezel from the system
chassis (Figure 7-15).
To replace the front bezel, reverse steps 1 through 5.
Chapter 7.6 Power Supply Subassembly Chassis
The power supply subassembly chassis consists of the following assemblies:
To remove the power supply subassembly chassis, complete the following steps:
1.Remove the outer access casing (see Section 7.3).
2.Place the computer on its side (see Figure 7-16).
3.Using a Torx screwdriver, loosen (DO NOT REMOVE) the nine mounting screws
that secure the power supply chassis to the system chassis (Figure 7-17).
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4.Remove only the two screws indicated in Figure 7-18.
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5.Remove the power supply subassembly chassis by lifting the rear portion of
the chassis upward.As this end is raised, lift the front portion of the
chassis until the entire power supply chassis is free of the system
chassis (Figure 7-19).
NOTE: Because the power supply connects directly to the system board, be
careful when removing the power supply subassembly chassis.
6.To completely remove the power supply subassembly chassis from the
Page 61
computer system chassis, disconnect the fan assembly and the automatic
power switching board (Figure 7-20).
7.Gently lift and remove the power supply subassembly from the system
chassis.
To replace the power supply subassembly chassis, reverse steps 1 through 6.
Chapter 7.7 Fan Assembly
To remove the fan assembly, complete the following steps:
1.Remove the power supply subassembly chassis (see Section 7.6).
2.Cut the two cable ties that secure the fan assembly power cable to the
system chassis.
3.Using a Phillips screwdriver, remove the two mounting screws and lift the
fan assembly from the system chassis (Figure 7-21).
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To replace the fan assembly, reverse steps 1 through 3.
Chapter 7.8 Automatic Power Switching Board (APS)
1.Remove the power supply subassembly chassis (see Section 7.6).
NOTE: Carefully remove all three connections to the APS board when
removing the power supply chassis.Refer to Figure 7-22 for an
illustration of the APS board.
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2.To remove the APS board, which is secured to the system chassis by four
PCB standoffs, press the top of each PCB standoff together, one at a time.
At the same time, carefully lift that portion of the APS board from the
system chassis.
Repeat this procedure until all board standoffs have been disconnected
from the APS board, then lift and remove the APS board from the system
chassis (Figure 7-23).
To replace the APS Board, complete the following steps:
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1.Slide the APS Board into place on the system
2.Press the four PCB standoffs into the holes in the board.
3.Hold the power supply subassembly at a 30 to 45 degree angle as shown in
Figure 7-24, and tie the three wire harnesses together with a ty-wrap.
When reassembling the APS board, be sure to reconnect the fan.Do not "pinch"
the harness wires between the power supply subassembly and the chassis; this
could interfere with the cooling system and result in overheating.
4.Reinstall the power supply subassembly chassis (see Section 7-6).
Chapter 7.9 High Voltage Access Plate
The high voltage access plate is located just above the video monitor and
power supply assemblies.
To remove the high voltage access plate, complete the following steps:
1.Remove the outer access casing (see Section 7.3).
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2.Using a Torx screwdriver, loosen (DO NOT REMOVE) the 11 mounting screws
that secure the high voltage monitor access plate to the system chassis.
Remove only the three mounting screws indicated in Figure 7-25.
3.Gently slide the high voltage access plate towards the power supply
chassis assembly and lift it up and away from the system chassis.
To replace the high voltage access plate, reverse steps 1 through 3.
Chapter 7.10 Board Slots Access Plate
The board slots access plate is located at the rear of the computer and covers
all installed controller and option boards.
To remove the board slots access plate, complete the following steps:
1.Remove the outer access casing (see Section 7.3).
2.Using a Torx screwdriver, loosen (DO NOT REMOVE) the seven mounting screws
that secure the board slots access plate to the system chassis.Remove
only the one screw indicated in Figure 7-26.
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3.Gently slide the board slots access plate to the right of the computer and
lift it up and away from the system chassis.
To replace the board slots access plate, reverse steps 1 through 3.
Chapter 7.11 Mass Storage Device Access Plate
The mass storage device access plate is located at the front of the system
chassis and covers all installed mass storage devices.
To remove the mass storage device access plate, complete the following steps:
1.Remove the outer access cover (See Section 7.3).
NOTE: It is not necessary to remove the mass storage device access plate
before removing the mass storage device enclosure.
2.Using a Torx screwdriver, remove the eight mounting screws that secure the
mass storage device access plate to the system chassis and the mass
storage device enclosure (Figure 7-27).
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3.Carefully lift the mass storage device access plate away from the system
chassis.
To replace the mass storage device access plate, reverse steps 1 through 3.
Chapter 7.12 System Memory Board Access Plate
To remove the system memory board access plate, complete the following steps:
1.Remove the outer access casing (see Section 7.3).
2.Turn over the system chassis as illustrated in Figure 7-28.
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3.Using a Torx screwdriver, loosen (DO NOT REMOVE) the seven mounting screws
that secure the system memory board access plate to the system chassis.
Remove only the one mounting screw indicated in Figure 7-29.
4.Carefully lift and remove the system memory board access plate from the
system chassis (Figure 7-29).
To replace the system memory board access plate, reverse steps 1 through 4.
Page 69
Chapter 7.13 Cable Tray Access Plate
To remove the cable tray access plate, complete the following steps:
1.Remove the outer access casing (see Section 7.3).
2.Remove the system memory board access plate (see Section 7.12).
3.Turn over the system chassis as illustrated in Figure 7-30.
4.Using a Torx screwdriver, loosen (DO NOT REMOVE) the seven Torx screws
that secure the cable tray access plate to the system chassis.Remove
only the two mounting screws noted in Figure 7-31.
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5.Carefully lift and remove the cable tray access plate from the system
chassis.
To replace the cable tray access plate, reverse steps 1 through 5.
Chapter 7.14 Multipurpose Controller Board
The Multipurpose Controller Board is located in slot J104 on the system board
(Figure 7-32).To remove the multipurpose controller board, complete the
following steps.
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1.Remove the board slots access plate (see Section 7.10).
2.Disconnect the mass storage device signal cable(s) as shown in
Figure 7-33.
NOTE: If a fixed disk drive is installed in the system chassis, you must
disconnect two signal cables.
3.Using a Torx screwdriver, remove the board retaining screw.Carefully
Page 72
lift the controller board up and out of the system board (Figure 7-34).
To replace the Multipurpose Controller Board, reverse steps 1 through 3.
Chapter 7.15 Video Display Controller Board
The Video Display Controller Board is located in slot J103 on the system board
(Figure 7-35).
Page 73
To remove the Video Display Controller Board, complete the following steps:
1.Remove the board slots access plate (see Section 7.10).
2.Remove the retaining screw that secures the Video Display Controller
Board.Then disconnect the video display signal cable (Figure 7-36).
3.Carefully lift the board up and out of its J103 connector location on the
system board (Figure 7-37).
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To replace the Video Display Controller Board, reverse steps 1 through 3.
The COMPAQ PORTABLE II Personal Computer may contain up to two option boards.
Option boards are always installed in the back two slots of the system
chassis.To remove a COMPAQ 512/2048 Kbyte Memory Expansion Board or any
other option board installed in the computer, complete the following steps:
1.Remove the outer access casing (See Section 7.3).
2.Disconnect any signal cables connected to the board.
3.Remove the retaining screw that secures the board to the system chassis.
4.Carefully lift the board up and out of its connector on the system board
(Figure 7-38).
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To replace the 512/2048 Kbyte Memory Expansion Board or other option boards,
reverse steps 1 through 4.
Chapter 7.17 Handle
To remove the handle from the computer, complete the following steps:
1.Remove the outer access casing (see Section 7.3).
2.Remove the board slots access plate (see Section 7.10).
3.Remove all controller and option boards installed (see Sections 7.14
through 7.16).
4.Using a Torx screwdriver, remove the two mounting screws that secure the
handle to the system chassis, and remove the handle system chassis
(Figure 7-39).
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To replace the handle, reverse steps 1 through 4.
Chapter 7.18 System Board
There are two versions of the system board for the COMPAQ PORTABLE II:
version 1 (Assy No. 000318) and version 2 (Assy No. 000324).The two system
boards differ in shape, memory chip locations, and jumper locations
(Figures 7-40 and 7-41).
Functionally both versions are identical; however, the version 2 system board
contains three gate array devices that consolidate the functions of several
devices from the earlier version making a smaller system board possible.
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To remove either system board, complete the following steps:
1.Remove the power supply subassembly chassis (see Section 7.6).
2.Remove the board slots access plate (see Section 7.10).
3.Remove all controller and option boards installed (see Sections 7.14
through 7.16).
4.Using Figure 7-42 as a reference, disconnect the mass storage
device power cable.
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5.Remove the system memory board access plate (see Section 7.12).
6.Remove the cable tray access plate (see Section 7.13).
7.Using Figure 7-43 as a reference, disconnect the keyboard power cable,
the video display unit power cable, and the speaker/brightness control
cable.
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8.Using a Torx screwdriver, remove the eight mounting screws that secure
the system board to the system chassis.
9. Carefully lift the system board from the System chassis (Figure 7-44).
To replace the system board, reverse steps 1 through 9.
If replacing a Version 1 board with a Version 2 board, the
speaker/brightness potentiometer assembly (PN 104185-001 no longer
available) should be replaced with an assembly containing a longer wiring
harness.Spare part kits containing version 2 boards include a
speaker/brightness potentiometer assembly.
NOTE: Be sure to pay special attention to the system board guide/clamp at the
rear of the chassis.
The lithium battery may explode if mishandled or stored improperly.Do not
abuse, disassemble, or incinerate.Use only replacement batteries supplied by
Compaq Computer Corporation (PN 104186-001).
To replace the battery, complete the following steps:
1.Replace the battery in the snap in connector.
2.Replace the cable tie.
3.Replace the 512/1536 Kbyte System Memory Board access plate (see
Section 7.12).
Chapter 7.20 512/1536 KByte System Memory Board
To remove the 512/1536 Kbyte System Memory Board, complete the following
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steps:
1.Remove the outer access casing (see Section 7.3).
2.Remove the Memory Expansion Board access plate (see Section 7.12).
3.The memory board is secured to the system board by six PCB standoffs.To
remove the memory board from the system board, press the top of each PCB
stand off together, one at a time.At the same time, gently lift that
portion of the memory board from the stand off.Repeat this procedure
until all PCB standoffs have been disconnected from the system memory
board.
4.Lift the disconnected memory board from the system board (Figure 7-46).
To replace the memory board, reverse steps 1 through 4.
Chapter 7.21 Memory Option
COMPAQ PORTABLE II Personal Computer memory chips can be installed on the
system board, the 512/2048 Kbyte Memory Expansion Board, or the 512/1536 Kbyte
System Memory Board.
To remove a memory chip, complete the following steps:
1.Remove the board that contains the memory chip to be replaced.For board
removal procedures, refer to one of the following sections.
oFor the 512/2048 Kbyte Memory Expansion Board removal and replacement
procedure refer to Section 7.16.
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oFor the system board removal and replacement procedure refer to
Section 7.18.
oFor the 512/1536 Kbyte System Memory Board removal and replacement
procedure, refer to Section 7.20.
NOTE: The RAM and ROM chip locations on the system boards differ from
those on the memory boards (See Figures 7-47 through 7-50).
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2.Using an IC removal tool, remove the defective RAM or ROM chip(s)
(Figure 7-51).
3.Using a special IC insertion tool, replace the defective RAM or ROM
chip(s) (Figure 7-52).
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4.Replace the memory board.
NOTE: After replacing the defective component, run DIAGNOSTICS to verify
proper operation of the computer.(Please consult the SUPPORT SOFTWARE
MAINTENANCE AND SERVICE GUIDE for current information on DIAGNOSTICS.)
Chapter 7.22 Mass Storage Device Subassembly
Mass storage device subassemblies for the COMPAQ PORTABLE II Personal
Computer consist of fixed disk drives and diskette drives.Refer to
Figure 7-53 for the location of each type of mass storage device subassembly.
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Mass Storage Device Subassembly Enclosure
To remove the mass storage device subassembly enclosure, complete the
following steps:
1.Remove the outer access casing (see Section 7.3).
2.Remove all installed controller and option boards (see
Sections 7.14 through 7.16).
3.Using a screwdriver, gently pry the drive bezel from the front bezel
(Figure 7-54).This exposes the installed mass storage devices.
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4.Using a Torx screwdriver, remove the two screws on the right side of the
system chassis and the four screws on the top of the mass storage device
enclosure.These screws secure the mass storage device subassembly
enclosure to the system chassis (Figure 7-55).
5.Slide the mass storage device subassembly enclosure forward a few inches
by reaching into the open system chassis area and pushing the enclosure
forward.This action will expose the mass storage power cables
(Figure 7-56).
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6.Disconnect the diskette drive and fixed disk drive power cable from the
system board (Figure 7-57).
7.Grasp the sides of the mass storage device subassembly enclosure firmly
and slide the enclosure out of the system chassis (Figure 7-58).
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To replace the mass storage device subassembly enclosure, reverse
steps 1 through 7.
Fixed Disk Drive
To remove the fixed disk drive assembly:
1.Remove the mass storage device subassembly enclosure (see
Section 7.22).
2.Using a Torx screwdriver, remove the two shoulder bolts and vibration
isolators from either side of the mass storage device subassembly
enclosure.Slide the fixed disk drive assembly enclosure out of the mass
storage device subassembly (Figure 7-59).
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NOTE: The fixed disk drive is mounted above the diskette drive.
To replace the fixed disk drive assembly, reverse steps 1 and 2.
Diskette Drive
To remove the diskette drive assembly, complete the following steps:
1.Remove the mass storage device subassembly enclosure (see
Section 7.22).
2.Using a Torx screwdriver, remove the two shoulder bolts that secure the
diskette disk drive assembly from either side of the mass storage device
subassembly enclosure (Figure 7-60).
3.Slide the diskette drive assembly out of the mass storage device
subassembly enclosure (Figure 7-60).
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NOTE: When removing the diskette drive, make sure the vibration isolators
are not lost.You need to reinstall all four isolators when replacing the
diskette drive assembly.
To replace the diskette drive assembly, reverse steps 1 through 3.
NOTE: When replacing a flip door style diskette drive with a push button
style diskette drive, you should also order a replacement drive bezel (PN
104059-001 (No longer available)) to provide a better fit for the new
diskette drive assembly.
Chapter 7.23 Speaker and Brightness Potentiometer
To remove the speaker and brightness potentiometer:
1.Remove the cable tray access plate (see Section 7.13).
2.Remove the mass store device enclosure (see Section 7.22).
3.Remove the front bezel (see Section 7.5).
4.The speaker is secured to the system chassis by a snap in mount and a
toe in mount that extend through the system chassis.Remove the speaker
by first disconnecting the speaker/brightness control connector from the
J114 position on the system board, then pressing the snap in mount
inward.At the same time, push the speaker out of the system chassis
(Figure 7-61).
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5.Remove the brightness potentiometer by first unscrewing the nut that
secures it to the system chassis, then push the brightness potentiometer
out of the system chassis (Figure 7-62).
To replace the speaker and the brightness potentiometer, reverse
steps 1 through 5.
Chapter 7.24 Video Display Unit
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To remove the video display unit (VDU), complete the following steps:
1.Remove the keyboard assembly (see Section 7.4).
2.Disconnect the VDU power cable (Figure 7-63).
3.Lower the computer so that it appears as illustrated Figure 7-64.
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4.Remove the high voltage access plate (see Section 7.9).
5.Remove the front bezel (see Section 7.5)
6.Disconnect the VDU signal cable from the VDU (Figure 7-65).
7.The VDU high voltage cable is secured to the system chassis by a
push mount with a snap connector at the end.Disconnect the VDU
high voltage cable by first unsnapping the push mount and then removing
the cable from its place inside the connector (Figure 7-66).
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8.The VDU sweep board is secured to the system chassis by five PCB stand off
mounts and one screw.Using a Torx screwdriver, remove the grounding
screw in the upper left corner of the VDU sweep board.To remove the VDU
sweep, grasp the board and gently slide it upward until the standoffs
clear the mounting holes.Once the VDU sweep board clears all standoffs,
slide the board out of the mounting holes and let it come to rest on the
side of the VDU (Figure 7-67).
9. Remove the four screws from the front of the video display unit (Figure 7-68).
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10.Remove the VDU from the system chassis by grasping the display screen and
the VDU sweep board and then sliding the unit until it is out of the
system chassis (Figure 7-69).
If replacement is necessary, this unit may be shipped back to Compaq Computer
Corporation packed only in a Compaq Spare VDU box.
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To replace the video display unit, reverse steps 1 through 10.
NOTE: When replacing the VDU assembly, replace the two top front mounting
screws first.This helps align the screen correctly.
The video display unit is fragile; be careful when handling it.Be careful
not to disturb the VDU adjustment potentiometers on the VDU sweep board and
not to break the display tube.
The jumper settings on the 512/2048 Kbyte Memory Expansion Board correspond
to the amount of random access memory installed in the four banks on the
option board.There are four possible memory configurations that expand the
memory address range from 1.0 megabyte to 3.0 megabytes.Figure 8-3 shows
the component layout for the 512/2048 Kbyte Memory Expansion Board.
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Refer to Tables 8-2 and 8-3 when setting the jumpers on the 512/2048 Kbyte
Memory Expansion Board.