Compaq 486, PORTABLE 486c Maintenance And Service Manual

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Notice
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.
Copyright 1991 Compaq Computer Corporation. All rights reserved. Printed in the USA
SLT is a trademark of Compaq Computer Corporation.
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 may be trademarks and/or registered trademarks of their respective companies.
MAINTENANCE AND SERVICE GUIDE COMPAQ PORTABLE 486c Personal Computer
First Edition (October 1991) Text Number 128987-001
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Chapter 1. Specifications
Introduction
This chapter provides physical, environmental, and performance specifications for the following COMPAQ PORTABLE 486c Personal Computer subsystems:
o System Unit o Full Function 101/102 Key Keyboard o Active Matrix Color VGA Display o Power Supply o 3 1/2 inch 1.44 Megabyte Diskette Drive o 210 and 120 Megabyte Fixed Disk Drives
Chapter 1.1 System Unit
=============================================================================
----------------------------------------------------------------------------­Dimensions
Height 11.0 inch 27.9 cm Width 15.6 inch 39.6 cm Depth 5.5 inch 13.9 cm
----------------------------------------------------------------------------­Weight (with keyboard)
Model 210 17.6 lb 7.9 kg Model 120 17.6 lb 7.9 kg
----------------------------------------------------------------------------­Environmental Requirements
U.S. Other
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Temperature
Operating 50oF to 104oF 10oC to 40oC Nonoperating -22oF to 140oF -30oC to 60oC
Relative Humidity (noncondensing)
Operating 20% to 80% 20% to 80%
Nonoperating 5% to 90% 5% to 90% Maximum Unpressurized Altitude
Operating 10,000 ft 3,050 m
Nonoperating 30,000 ft 9,150 m
----------------------------------------------------------------------------­Cooling 12 VDC fan 12 VDC fan
----------------------------------------------------------------------------­Shock 40g, 11 ms, half sine
(nonoperating)
----------------------------------------------------------------------------­Vibration
Operating 0.25g, 5 to 500 Hz,
1/2 octave/min sweep
Nonoperating 1.0g, 5 to 500 Hz,
1/2 octave/min sweep
=============================================================================
Chapter 1.2 Keyboard
=============================================================================
----------------------------------------------------------------------------­Dimensions
Height 1.2 inch 3.0 cm Depth 7.4 inch 18.7 cm Width 15.7 inch 39.8 cm
----------------------------------------------------------------------------­Weight 2.65 lb 1.2 kg
----------------------------------------------------------------------------­Number of Keys 101 102
----------------------------------------------------------------------------­Cable
Compressed 24.0 inch 60.9 cm Extended 46.5 inch 118.1 cm
----------------------------------------------------------------------------­Interface 6 pin mini DIN 6 pin mini DIN
----------------------------------------------------------------------------­Power
Volts 4.5 to 5.5 VDC 4.5 to 5.5 VDC Current 300 mA 300 mA
=============================================================================
English Other
connector connector
Chapter 1.3 Active Matrix Color Display
=============================================================================
----------------------------------------------------------------------------­Dimensions (viewing area)
Height 6.2 inch 15.8 cm
U.S. Other
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Width 8.3 inch 21.1 cm
----------------------------------------------------------------------------­Diagonal Size 10.4 inch 26.4 cm
----------------------------------------------------------------------------­Mounting Internal Internal
----------------------------------------------------------------------------­Tilt Angle -5oF to 32oF -5oC to 32oC
----------------------------------------------------------------------------­Display Active Matrix Active Matrix
Color VGA, TFT Color VGA, TFT
----------------------------------------------------------------------------­Color Capability 256, 16 shades 256, 16 shades
per primary color per primary color
----------------------------------------------------------------------------­Brightness Adjustable Adjustable
----------------------------------------------------------------------------­Maximum Pixel Resolution (Text and Graphics) 640 x 480 640 x 480
640 x 400 640 x 400 640 x 350 640 x 350
----------------------------------------------------------------------------­Operating Frequency 25 MHz 25 MHz
----------------------------------------------------------------------------­VDC Input
Nominal Voltage 5 VDC 12 VDC Current Maximum 150 mA 420 mA Power Maximum 0.75W 5.04W
==============================================================================
Chapter 1.4 Power Supply
=============================================================================
----------------------------------------------------------------------------­Input Requirements
Nominal Voltage 120 VAC 240 VAC Maximum Range Voltage 100 to 120 VAC 220 to 240 VAC Line Frequency 60 Hz 50 Hz Current 4A 2A Fuse 5A 5A
----------------------------------------------------------------------------­Operating Power 125W * 125W *
----------------------------------------------------------------------------­Line Voltage Switching Automatic Automatic
----------------------------------------------------------------------------­Cooling 2 speed fan, 2 speed fan,
----------------------------------------------------------------------------­Operating Temperature 41oF to 104oF 5oC to 40oC
----------------------------------------------------------------------------­VDC Output
Nominal Voltage 5V 12V -12V Current Minimum 1.5A 0.1A 0A Current Maximum 12A 4.2A 1A Maximum Peak Current 18A 6A 1A Regulation Tolerance 3% 5% 5%
-----------------------------------------------------------------------------
U.S. Other
thermostatically thermostatically controlled controlled
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NOTE: These values are maximum values based on nominal operating conditions for temperature, line voltage, frequency, and altitude.
----------------------------------------------------------------------------­* 60W maximum available through EISA expansion slots.
=============================================================================
Chapter 1.5 Diskette Drive
=============================================================================
-----------------------------------------------------------------------------
Diskette Size 3 1/2 inch
Capacity Per Diskette (high/low) 1.44 MB/720 KB
LED Indicators
Read/Write (high density) Green Read/Write (low density) Orange
Drives Supported One
Drive Height 0.75 inch (1.9 cm)
Drive Rotation (rpm) 300
Transfer Rate (bps) (high/low) 500K/250K
Bytes Per Sector 512
Sectors Per Track (high/low) 18/9
1.44 MB
Tracks Per Side (high/low) 80/80
Access Times
Track to Track 3 ms Average 80 ms Settling Time 15 ms Latency Average 100 ms
Cylinders (high/low) 80/80
Read/Write Heads 2 =============================================================================
Chapter 1.6 Fixed Disk Drives
=============================================================================
-----------------------------------------------------------------------------
Standard Configurations Model 210 Model 120
Formatted Capacity 212.6 MB 121.5 MB
210 MB 120 MB
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Drives Supported One One
Form Factor 3 1/2 inch 3 1/2 inch
Drive Height 1 inch 1 inch
Drive Weight 1.3 lb 1.3 lb
Drive Type (logical) 51 50
Drive Speed 4500 rpm 3399 rpm
Transfer Rate (per second)
Head 20 MB 12 MB Buffer (max) 5 MB 4.5 MB
Sector Interleave 1:1 1:1
Seek Times
Track to Track 3 ms 8 ms Average 12 ms 19 ms Maximum 30 ms 35 ms
Cylinders
Physical 2119 1522 Logical 683 760
Read/Write Heads
Physical 4 4 Logical 16 8
Sectors Per Track
Physical 49 40 Logical 38 + 1 spare 39 + 1 spare
Bytes Per Sector 512 512 =============================================================================
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Chapter 2. Power On Self Test (POST)
Introduction
This chapter lists the subassemblies checked by the Power On Self Test (POST) and briefly describes the types of error codes that can occur. The chapter also includes problem isolation procedures and a flowchart for quick reference.
Chapter 2.1 POST
POST is a series of diagnostic tests that runs automatically on the COMPAQ PORTABLE 486c Personal Computer when it is turned on.
POST checks the following subassemblies to ensure that the computer system is functioning properly:
o Processor Board o Memory Module o Keyboard o Controller Circuitry o Video Circuitry o Fixed Disk Drive o Diskette Drive
If POST finds an error in the computer, an error condition is indicated by an audible and/or visual message. See Chapter 3, "Error Messages and Codes," for an explanation of the error codes and a recommended course of action.
Chapter 2.2 Preliminary Steps
If you encounter an error condition, complete the following steps before starting the problem isolation procedures:
1. Turn off power to the computer.
2. Disconnect any external devices. Do not disconnect the printer if you
want to test the printer or use it to log error messages.
3. Install all appropriate loopback plugs and terminating plugs for complete
testing.
4. Clear the power on password, if it is preset by the user. You will know
that the power on password is set when a key icon (0--m) appears on the screen when POST completes. If this occurs, you must enter the password to continue.
If you do not have access to the password, you must disable the power on password feature by setting the power on password switch (see section
2.3, "Clearing Power on Password").
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5. Access the fixed disk drive.
You will know that the fixed disk drive password is set when the DriveLock icon (see illustration of DriveLock icon below) appears on the screen. If this occurs, you must enter the fixed disk drive password to continue.
IMPORTANT: It is not necessary to access the fixed disk drive in order to run the Diagnostics diskette; however, complete system testing cannot be done without access to the complete system.
The user must clear the fixed disk drive password or give you access before servicing can be performed.
6. Position the brightness and volume controls approximately in the center
of their range.
7. Insert the Diagnostics diskette into drive A.
8. Turn on the computer.
9. Follow the procedures of the Problem Isolation Flowchart, section 2.4.
Refer to Chapter 3, "Error Messages and Codes," for detailed information on problem isolation.
Chapter 2.3 Clearing Power On Password
To clear the power on password feature, reset the power on password switch (SW5) located on the I/O board. To do so, complete the following steps:
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1. Disconnect the AC power.
2. Disassemble the computer to reach the I/O board (refer to Chapter 5).
3. Locate the power on password switch (SW5) on the I/O board; set the
switch to ON (Figure 2-1).
4. Reconnect AC power.
5. Turn on the computer and allow it to complete POST.
6. Turn the computer off.
7. Set switch SW5 to OFF.
8. Disconnect AC power.
9. Reassemble the computer (refer to Chapter 5).
10. Reconnect the AC power.
11. Turn on the computer and allow it to complete POST. If the key icon
(o--m) does not appear when POST completes, the power on password has been cleared.
Chapter 2.4 Problem Isolation Flowchart
The problem isolation flowchart provides a quick reference for identifying and correcting problems that may occur during POST. The flowchart gives troubleshooting procedures for identifying malfunctions. It also directs you to the Diagnostics chapter in the SUPPORT SOFTWARE MAINTENANCE AND SERVICE GUIDE and to Chapter 3, "Error Messages and Codes," for more detailed
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troubleshooting information.
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Chapter 3. Error Messages and Codes
This chapter contains Power On Self Test (POST) messages, Diagnostic error codes, and memory error codes for the COMPAQ PORTABLE 486c Personal Computer.
The messages and codes appear in tables that list the message or error code, a description of the error or its probable cause, and the action recommended to resolve the error condition.
Chapter 3.1 Power On Self Test Messages
An error message results if a problem is encountered during POST, which runs automatically when the system is turned on.
Table 3-1 lists the messages for POST, the audible (beep) messages, probable causes, and recommended actions.
Table 3-1. Power On Self Test Messages ============================================================================= Message Beeps Probable Cause Recommended Action
-----------------------------------------------------------------------------
101 - ROM Error 1 Long, System ROM The following steps
1 Short checksum apply to error
101 - I/O ROM Error 1 Long, Option ROM 1. Inspect the ROM
1 Short checksum placement.
-----------------------------------------------------------------------------
102 - Processor None Processor board: Replace the processor Board Failure DMA timers, etc. board.
-----------------------------------------------------------------------------
162 - System Options 2 Short Configuration Run COMPAQ EISA Not Set incorrect or no Configuration utility.
-----------------------------------------------------------------------------
163 - Time and 2 Short Invalid time or Run COMPAQ EISA Date Not Set date in Configuration utility.
-----------------------------------------------------------------------------
164 - Memory Size 2 Short Configuration Run COMPAQ EISA Error memory size Configuration utility.
-----------------------------------------------------------------------------
170 - Expansion 1 Short EISA board not Run COMPAQ EISA Device ready after Configuration utility
-----------------------------------------------------------------------------
172 - EISA 1 Short Nonvolatile Run COMPAQ EISA Configuration configuration Configuration utility Nonvolatile memory corrupt or for error codes 172-xx Memory jumper installed through 177-xx.
code 101:
2. Verify the correct ROM.
3. Replace the ROM.
diskette drive
configuration memory
incorrect
power on delay
173 - EISA Slot ID 1 Short Board replaced,
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Mismatch configuration not
updated
174 - EISA 1 Short EISA board Configuration/ not found Slot Mismatch
175 - EISA 1 Short EISA board added, Configuration/ configuration not Slot Mismatch updated
176 - Slot with 1 Short EISA board in Unreadable ID slot that should
contain ISA board
177 - Configuration 1 Short Incomplete EISA Not Complete configuration
----------------------------------------------------------------------------­Message Beeps Probable Cause Recommended Action
----------------------------------------------------------------------------­178 - Processor 1 Short System board type Run COMPAQ EISA Configuration invalid or step Configuration utility.
does not match configuration memory
----------------------------------------------------------------------------­XX000Y ZZ * None RAM failure 1. Replace the 201 - Memory Error memory module
(see Figure 3-1).
2. Replace the processor board.
----------------------------------------------------------------------------­XX000Y ZZ * None Memory failure Replace the 203 - Memory processor board. Address Error
----------------------------------------------------------------------------­205 - Memory Error None Cache Memory Run Diagnostics. XXYYYYY controller or ZZZZZZZZ RAM failure
----------------------------------------------------------------------------­301 - Keyboard None Keyboard 1. Check that keyboard Error failure is connected.
2. Replace the keyboard.
----------------------------------------------------------------------------­303 - Keyboard None Processor board, Replace the keyboard, Controller Error keyboard, or mouse or I/O board.
mouse
----------------------------------------------------------------------------­304 - Keyboard or None Keyboard or 1. Replace the System Unit processor board keyboard. Error 2. Replace the
processor board.
----------------------------------------------------------------------------­501 - Display 1 Long, Video display Replace the video board Adapter Failure 2 Short controller
----------------------------------------------------------------------------­Message Beeps Probable Cause Recommended Action
----------------------------------------------------------------------------­601 - Diskette None Diskette Controller 1. Replace the power Controller Error circuitry distribution board
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and retest.
2. Run Diagnostics.
3. Replace the I/O board.
----------------------------------------------------------------------------­605 - Diskette Drive 2 Short Mismatch in Run COMPAQ EISA Type Error drive type Configuration utility.
----------------------------------------------------------------------------­610 - External None External Storage Turn on External Storage Module Module connected Storage Module or Failure. Hit but turned off disconnect from F1 when ready. computer.
----------------------------------------------------------------------------­701 - Coprocessor None Coprocessor Replace processor Error board.
----------------------------------------------------------------------------­1151 - Comm Port 1 2 Short Added or removed Run COMPAQ EISA Configuration modem, or second Configuration utility Error modem board for error codes
1151 through 1154.
1152 - Comm Port 2 2 Short Added or removed Configuration modem, or second Error modem board
1153 - Comm Port 3 2 Short Added or removed Configuration modem, or second Error modem board
1154 - Comm Port 4 2 Short Added or removed Configuration modem, or second Error modem board
----------------------------------------------------------------------------­Message Beeps Probable Cause Recommended Action
----------------------------------------------------------------------------­1771 - Primary Disk 2 Short Internal and Run Diagnostics. Port Address external fixed disk Assignment drive controllers Conflict are assigned to the
primary address
----------------------------------------------------------------------------­1772 - Secondary 2 Short Internal and Run Diagnostics. Disk Port Address external fixed disk Assignment drive controllers Conflict are assigned to the
secondary address
----------------------------------------------------------------------------­1780 - Disk 0 None Fixed disk drive/ 1. Run Diagnostics. Failure format error 2. Check and/or
replace the power distribution board.
3. Replace the fixed disk drive.
----------------------------------------------------------------------------­1781 - Disk 1 None Fixed disk drive/ 1. Run Diagnostics. Failure format error 2. Check and/or
replace the power distribution board.
3. Replace the fixed disk drive.
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----------------------------------------------------------------------------­1782 - Disk None Fixed disk drive 1. Run Diagnostics. Controller controller error 2. Check and/or Failure replace the power
distribution board.
3. Replace the fixed disk drive.
----------------------------------------------------------------------------­Message Beeps Probable Cause Recommended Action
----------------------------------------------------------------------------­1790 - Disk 0 Error None Fixed disk drive 1. Run Diagnostics.
error or wrong 2. Replace the drive type drive.
----------------------------------------------------------------------------­1791 - Disk 1 Error None Fixed disk drive 1. Run Diagnostics.
error or wrong 2. Replace the drive type drive.
----------------------------------------------------------------------------­XX000Y ZZ Parity None Parity RAM Run Diagnostics. Check 2 failure
----------------------------------------------------------------------------­Audible 1 Short Power on None.
successful
----------------------------------------------------------------------------­Audible 2 Short Power on None.
successful
----------------------------------------------------------------------------­(RESUME = None As indicated Press F1 key "F1" KEY) to continue. =============================================================================
Chapter 3.2 Diagnostic Error Codes
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Diagnostic error codes occur if the system recognizes a problem while running the Diagnostics program (refer to the SUPPORT SOFTWARE MAINTENANCE AND SERVICE GUIDE for additional information on running the Diagnostics software). These error codes help identify possible defective subassemblies. Tables 3-2 through 3-12 list possible error codes, a description of the error condition, and the action required to resolve the error 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 whether the error condition has been corrected. If the error code reappears, perform the next step, then run the Diagnostics program again. Follow this procedure until the Diagnostics program no longer detects an error condition.
The error codes appear in an AYY XX or AAYY XX format.
A or AA = number that represents faulty assembly YY = test or action that failed XX = a specific problem
Example: Error code 610-21 shows that the diskette drive failed to get change line status.
For assistance in the removal and replacement of a particular subassembly, see Chapter 5, "Removal and Replacement Procedures."
Table 3-2. Processor Test Error Codes ============================================================================= Error Recommended Code Description Action
----------------------------------------------------------------------------­101 - 01 16 bit CPU failed Replace the processor board
and retest for error codes
101 - 02 32 bit CPU failed 101 - xx.
101 - 50 BIOS dispatch of processor
101 - 51 Processor is unavailable
or non existent
101 - 52 Time out waiting for
completion of test
101 - 53 Failure to terminate processor
101 - 54 Time out waiting for serial
semaphore
101 - 56 Unexpected interrupt occurred
during test
101 - 91 16 bit multiplication, expected
101 - 92 32 bit multiplication expected
101 - 93 16 bit multiplication
unexpected
101 - 94 32 bit multiplication
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unexpected
101 - 95 Coprocessor and processor
board conflict
101 - 96 Refer to Authorized Compaq
Dealer Service Bulletin No. 84.
----------------------------------------------------------------------------­Error Recommended Code Description Action
----------------------------------------------------------------------------­102 - 01 Coprocessor initial status The following steps apply
word incorrect to error codes 102 - xx:
1. Run COMPAQ EISA
102 - 02 Coprocessor initial control Configuration utility.
word incorrect 2. Replace the processor
board and retest.
102 - 03 Coprocessor
tag word not all ones
102 - 04 Coprocessor tag
word not all zeros
102 - 05 Coprocessor exchange
command failed
102 - 06 Coprocessor masked
exception incorrectly handled
102 - 07 Coprocessor unmasked
exception incorrectly handled
102 - 08 Coprocessor wrong mask
bit set in status register
102 - 09 Coprocessor unable to
store real number
102 - 10 Coprocessor real number
calculation test failed
102 - 11 Coprocessor speed test
failed
102 - 12 Coprocessor pattern test failed
102 - 14 Switch indicates no numeric
coprocessor present
102 - 15 Coprocessor is inoperative
----------------------------------------------------------------------------­Error Recommended Code Description Action
----------------------------------------------------------------------------­103 - 01 DMA page registers test Replace the processor
failed board and retest for
error codes 103 - xx
103 - 02 DMA byte controller test through 114 - xx.
failed
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103 - 03 DMA word controller test
failed
104 - 01 Interrupt controller master
test failed
104 - 02 Interrupt controller slave
test failed
104 - 03 Interrupt controller software
RTC is inoperative
105 - 01 Port 61 bit 6 not at zero
105 - 02 Port 61 bit 5 not at zero
105 - 03 Port 61 bit 3 not at zero
105 - 04 Port 61 bit 1 not at zero
105 - 05 Port 61 bit 0 not at zero
105 - 06 Port 61 bit 5 not at one
105 - 07 Port 61 bit 3 not at one
105 - 08 Port 61 bit 1 not at one
----------------------------------------------------------------------------­Error Recommended Code Description Action
----------------------------------------------------------------------------­105 - 09 Port 61 bit 0 not at one Replace the processor board
and retest for error codes
105 - 10 Port 61 I/O test failed 103 - xx through 114 - xx.
105 - 11 Port 61 bit 7 not at zero
105 - 12 Port 61 bit 2 not at zero
105 - 13 No interrupt generated
by failsafe timer
105 - 14 NMI not triggered by
failsafe timer
107 - 01 CMOS RAM test failed
107 - 02 NOVRAM failed
107 - 03 Unable to restore extended
non volatile memory contents
108 - 02 CMOS interrupt test failed
108 - 03 CMOS interrupt test, CMOS
not properly initialized
109 - 01 CMOS clock load data test
failed
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109 - 02 CMOS clock rollover test
failed
109 - 03 CMOS clock test, CMOS not
properly initialized
----------------------------------------------------------------------------­Error Recommended Code Description Action
----------------------------------------------------------------------------­110 - 01 Programmable timer load Replace the processor board
data test failed and retest for error codes
103 - xx through 114 - xx.
110 - 02 Programmable timer dynamic
test failed
110 - 03 Programmable Timer No. 2
load data test failed
111 - 01 Refresh detect test failed
112 - 01 Speed test slow mode out
of range
112 - 02 Speed test mixed mode out
of range
112 - 03 Speed test fast mode out
of range
112 - 04 Speed test unable to enter
slow mode
112 - 05 Speed test unable to enter
mixed mode
112 - 06 Speed test unable to enter
fast mode
112 - 07 Speed test system error
112 - 08 Speed test unable to enter
auto mode
----------------------------------------------------------------------------­Error Recommended Code Description Action
----------------------------------------------------------------------------­112 - 09 Speed test unable to enter Replace the processor board
high mode and retest for error codes
103 - xx through 114 - xx.
112 - 10 Speed test high mode out
of range
112 - 11 Speed test auto mode out
of range
112 - 12 Speed test variable speed
mode inoperative
112 - 13 Failed Cache speed test
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113 - 50 BIOS dispatch of processor
113 - 51 Processor is unavailable
or nonexistent
113 - 52 Time out waiting for
completion of test
113 - 54 Time out waiting for serial
semaphore
113 - 56 Unexpected interrupt
occurred during test
114 - 01 Speaker test failed =============================================================================
Table 3-3. Memory Test Error Codes ============================================================================= Error Recommended Code Description Action
----------------------------------------------------------------------------­201 - 01 Memory machine ID test The following steps apply
failed to error codes 201 - xx
through 202 - xx:
1. Replace the system ROM
201 - 02 Memory machine type and retest.
test failed 2. Replace the processor
board and retest.
201 - 03 Memory machine ID
and type test failed
202 - xx ROM checksum test failed
202 - 01 Test failed
202 - 02 Failed RAM/ROM map
test
202 - 03 Failed RAM/ROM protect
test
202 - 04 System RAM/ROM
checksum test failed
----------------------------------------------------------------------------­203 - xx RAM write/read test The following steps apply
failed to error codes 203 - xx
through 211 - xx:
203 - 01 Memory write/read test 1. Replace the memory
module and retest.
203 - 02 Error during saving 2. Replace the processor
program memory in board and retest. write/read test
203 - 03 Error during restore of
memory in write/read test
204 - xx RAM address test failed
204 - 01 Memory address test
failed
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204 - 02 Error during saving
program memory in address test
----------------------------------------------------------------------------­Error Recommended Code Description Action
----------------------------------------------------------------------------­204 - 03 Error during restore of The following steps apply
program memory in to error codes 203 - xx address test through 211 - xx:
1. Replace the memory
204 - 04 A20 address test failed module and retest.
2. Replace the processor
204 - 05 Page hit address test board and retest.
failed
205 - 01 Walking 1/0 test failed
205 - 02 Error during saving
program memory in walking 1/0 test
205 - 03 Error during restore of
program memory in walking 1/0 test
205 - 04 Insufficient memory
to perform test
206 - xx Increment pattern test
failed
208 - 01 Memory refresh test
failed
208 - 02 Error during saving
program memory in refresh test
208 - 03 Error during restore
program memory in fresh test
----------------------------------------------------------------------------­Error Recommended Code Description Action
----------------------------------------------------------------------------­210 - xx Random Pattern Test The following steps apply
Failed to error codes 203 - xx
through 211 - xx:
210 - 01 Data read from block did 1. Replace the memory
not match data written module and retest.
2. Replace the processor
210 - 02 Scan of test block prior to board and retest.
testing
210 - 05 Inverted pattern compare,
RAM correct
210 - 10 Mapping LIM block, LIM
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page not present
211 - xx Random Pattern Test
211 - 01 Memory random pattern
test failed
211 - 02 Error during saving program
memory and random pattern in write/read test
211 - 03 Error during restore of
program memory and random pattern in write/read test
211 - 04 Insufficient memory to
perform test
211 - 05 Inverted pattern compare,
but RAM correct
=============================================================================
Table 3-4. Keyboard Test Error Codes ============================================================================= Error Recommended Code Description Action
----------------------------------------------------------------------------­301 - 01 Keyboard short test, The following steps apply
8042 self test failed to error codes 301 - xx
through 304 - xx:
301 - 02 Keyboard short test, 1. Check the keyboard
interface test failed connection. If
disconnected, turn off
301 - 03 Keyboard short test, echo the computer and
test failed connect the keyboard.
2. Replace the keyboard
301 - 04 Keyboard short test failed and retest.
3. Replace the I/O board
302 - 01 Keyboard long test failed and retest.
303 - 01 Keyboard LED test, 8042
self test failed
303 - 02 Keyboard LED test, reset
test failed
303 - 03 Keyboard LED test, reset
test failed
303 - 04 Keyboard LED test, LED
command test failed
303 - 05 Keyboard LED test, LED
command test failed
303 - 06 Keyboard LED test, LED
command test failed
303 - 07 Keyboard LED test, LED
command test failed
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----------------------------------------------------------------------------­Error Recommended Code Description Action
----------------------------------------------------------------------------­303 - 08 Keyboard LED test, The following steps apply
command byte restore to error codes 301 - xx test failed through 304 - xx:
1. Check the keyboard
303 - 09 Keyboard LED test, LEDs connection. If
failed to light disconnected, turn
off the computer and
304 - 01 Keyboard typematic test connect the keyboard.
failed 2. Replace the keyboard
and retest.
304 - 02 Unable to enter mode 3 3. Replace the I/O board
and retest.
304 - 03 Incorrect scan code from
keyboard
304 - 04 No make code observed
304 - 05 Unable to disable typematic
feature
304 - 06 Unable to return to
normal mode
=============================================================================
Table 3-5. Parallel Printer Test Error Codes ============================================================================= Error Recommended Code Description Action
----------------------------------------------------------------------------­401 - 01 Printer failed or not The following steps apply
connected to error codes 401 - xx
through 403 - xx:
402 - xx Printer port 1. If a printer is
connected, be sure it
402 - 01 Printer data register is turned ON and in
failed ONLINE mode.
2. Replace the printer
402 - 02 Printer control register cable and/or printer
failed and retest.
3. Replace the I/O board
402 - 03 Printer data and control and retest.
register failed
402 - 04 Printer loopback failed
402 - 05 Printer loopback and data
failed
402 - 06 Printer loopback and control
register failed
402 - 07 Printer loopback, data, and
control register failed
402 - 08 Printer interrupt test failed
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402 - 09 Printer interrupt and data
register failed
402 - 10 Printer interrupt and control
register failed
----------------------------------------------------------------------------­Error Recommended Code Description Action
----------------------------------------------------------------------------­402 - 11 Printer interrupt, data, and The following steps apply
control register failed to error codes 401 - xx
through 403 - xx:
402 - 12 Printer interrupt and 1. If a printer is
loopback failed connected, be sure it
is turned ON and in
402 - 13 Printer interrupt, loopback, ONLINE mode.
and data register failed 2. Replace the printer
cable and/or printer
402 - 14 Printer interrupt, loopback, and retest.
and control register failed 3. Replace the I/O board
and retest.
402 - 15 Printer interrupt, loopback,
data, and control register failed
402 - 16 Printer unexpected interrupt
received
402 - 25 Printer multiple interrupt
402 - 26 Printer multiple interrupt
403 - 01 Printer pattern test failed =============================================================================
Table 3-6. Active Matrix Color Display Test Error Codes ============================================================================= Error Recommended Code Description Action
----------------------------------------------------------------------------­501 - 01 Video Controller Test Replace the video board
Failed and retest for error
codes 501 - xx through
502 - 01 Video Memory Test 516 - xx.
Failed
503 - 01 Video Attribute Test
Failed
504 - 01 Video Character Set Test
Failed
505 - 01 Video 80 x 25 Mode
9 x 1 Character Cell Test Failed
506 - 01 Video 80 x 25 Mode
8 x 8 Character Cell Test Failed
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507 - 01 Video 40 x 25 Mode
Test Failed
508 - 01 Video 320 x 200 Mode
Color Set 0 Test Failed
509 - 01 Video 320 x 200 Mode Color
Set 1 Test Failed
510 - 01 Video 640 x 200 Mode
Test Failed
511 - 01 Video Screen Memory
Page Test Failed
512 - 01 Video Gray Scale Test
Failed
514 - 01 Video White Screen Test
Failed
516 - 01 Video Noise Pattern Test
Failed
=============================================================================
Table 3-7. Diskette Drive Test Error Codes ============================================================================= Error Recommended Code Description Action
----------------------------------------------------------------------------­600 - xx Diskette ID drive types The following steps apply
test failed to error codes 600 - xx
through 610 - xx:
601 - xx Diskette format failed 1. Replace the diskette
and retest.
602 - xx Diskette read test failed 2. Replace the diskette
drive and retest.
603 - xx Diskette write, read, 3. Replace the I/O board
compare test failed and retest.
4. Replace the power
604 - xx Diskette random seek distribution board
test failed and retest.
605 - xx Diskette ID media failed
606 - xx Diskette speed test failed
607 - xx Diskette wrap test failed
608 - xx Diskette write protect
test failed
609 - xx Diskette reset controller
test failed
610 - xx Diskette change line test
failed
610 - 01 Exceeded maximum
soft error limit
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610 - 02 Exceeded maximum
hard error limit
610 - 03 Previously exceeded
maximum soft error limit
----------------------------------------------------------------------------­Error Recommended Code Description Action
----------------------------------------------------------------------------­610 - 04 Previously exceeded The following steps apply
maximum hard error limit to error codes 600 - xx
through 610 - xx:
610 - 05 Failed to reset controller 1. Replace the diskette
and retest.
610 - 06 Fatal error while reading 2. Replace the diskette
drive and retest.
610 - 07 Fatal error while writing 3. Replace the I/O board
and retest.
610 - 08 Failed compare of 4. Replace the power
write/read buffers distribution board and
retest.
610 - 09 Failed to format a track
610 - 10 Failed sector wrap test
610 - 20 Failed to get drive type
610 - 21 Failed to get change
line status
610 - 22 Failed to clear change
line status
610 - 23 Failed to set drive type
in ID media
610 - 24 Failed to read diskette
media
610 - 25 Failed to verify diskette
media
610 - 26 Failed to read media in
speed test
610 - 27 Failed speed limits
610 - 28 Failed write protect test
----------------------------------------------------------------------------­Error Recommended Code Description Action
----------------------------------------------------------------------------­697 - 00 Diskette type error The following steps apply
to error codes 697 - xx and 698 - xx:
698 - 00 Diskette drive speed 1. Replace the diskette
not within limits and retest.
2. Replace the diskette drive and retest.
Page 32
3. Check and/or replace drive cable and retest.
4. Replace the I/O board and retest.
----------------------------------------------------------------------------­699 - 00 Diskette drive/media ID 1. Replace the media.
error, rerun COMPAQ 2. Run COMPAQ EISA EISA Configuration utility Configuration utility.
=============================================================================
Table 3-8. Serial Test Error Codes ============================================================================= Error Recommended Code Description Action
----------------------------------------------------------------------------­1101 - 01 Serial Port Test: UART Replace the I/O board and
DLAB bit failure retest for error codes
1101 - xx through
1101 - 02 Serial Port Test; line 1109 - xx.
input or UART fault
1101 - 03 Serial Port Test; address
line fault
1101 - 04 Serial Port Test; data
line fault
1101 - 05 Serial Port Test; UART
control signal failure
1101 - 06 Serial Port Test; UART
THRE bit failure
1101 - 07 Serial Port Test; UART
DATA READY bit failure
1101 - 08 Serial Port Test; UART
TX/RX buffer failure
1101 - 09 Serial Port Test; INTERRUPT
circuit failure
1101 - 10 Serial Port Test; COM1 set
to invalid interrupt
1101 - 11 Serial Port Test; COM2 set
to invalid interrupt
----------------------------------------------------------------------------­Error Recommended Code Description Action
----------------------------------------------------------------------------­1101 - 12 Serial Port Test; DRIVER/ Replace the I/O board and
RECEIVER control signal retest for error codes failure 1101 - xx through
1109 - xx.
1101 - 13 Serial Port Test; UART
control signal interrupt failure
Page 33
1101 - 14 Serial Port Test;
DRIVER/RECEIVER data failure
1101 - 15 Serial port test modem
detection
1101 - 16 Serial port test, modem
ROM checksum
1101 - 17 Serial port test, tone
detection
1101 - 18 Serial port test, COM3
set to invalid interrupt
1101 - 19 Serial port test, COM4
set to invalid interrupt
1109 - 01 Clock register initialization
failure
1109 - 02 Clock register rollover
failure
----------------------------------------------------------------------------­Error Recommended Code Description Action
----------------------------------------------------------------------------­1109 - 03 Clock reset failure Replace the I/O board and
retest for error codes
1109 - 04 Input line or clock failure 1101 - xx through
1109 - xx.
1109 - 05 Address line fault
1109 - 06 Data line fault =============================================================================
Table 3-9. Modem Test Error Codes ============================================================================= Error Recommended Code Description Action
----------------------------------------------------------------------------­1201 - xx Modem Internal The following steps apply
Loopback Test to error codes 1201 - xx
through 1210 - xx:
1201 - 01 UART DLAB bit failure 1. Refer to modem
documentation for
1201 - 02 Line input or UART Configuration utility
failure procedures.
2. Check the modem line.
1201 - 03 Address line fault 3. Replace the modem
and retest.
1201 - 04 Data line fault
1201 - 05 UART control signal failure
1201 - 06 UART THRE bit failure
1201 - 07 UART DATA READY bit
failure
Page 34
1201 - 08 UART TX/RX buffer failure
1201 - 09 INTERRUPT circuit
failure
1201 - 10 COM1 set to invalid
interrupt
1201 - 11 COM2 set to invalid
interrupt
1201 - 12 DRIVER/RECEIVER
control signal failure
----------------------------------------------------------------------------­Error Recommended Code Description Action
----------------------------------------------------------------------------­1201 - 13 UART control signal The following steps apply
interrupt failure to error codes 1201 - xx
through 1210 - xx:
1201 - 14 DRIVER/RECEIVER 1. Refer to modem
data failure documentation for
Configuration utility
1201 - 15 Modem detection failure procedures.
2. Check the modem line.
1201 - 16 Modem ROM; checksum 3. Replace the modem and
failure retest.
1201 - 17 Tone detection failure
1202 - xx Internal Modem Test
1202 - 01 Modem timed out waiting
for SYNC (local loopback mode)
1202 - 02 Modem timed out waiting
for response (local loopback mode)
1202 - 03 Modem exceeded data
block retry limit (local loopback mode)
1202 - 11 Modem timed out waiting
for SYNC (analog loopback originate mode)
1202 - 12 Modem timed out waiting
for modem response (analog loopback originate mode)
----------------------------------------------------------------------------­Error Recommended Code Description Action
----------------------------------------------------------------------------­1202 - 13 Modem exceeded data block The following steps apply
retry limit (analog to error codes 1201 - xx loopback originate mode) through 1210 - xx:
1. Refer to modem
Page 35
1202 - 21 Modem timed out waiting documentation for
for SYNC (analog loopback Configuration utility answer mode) procedures.
2. Check the modem line.
1202 - 22 Modem timed out waiting 3. Replace the modem
for modem response (analog and retest. loopback answer mode)
1202 - 23 Modem exceeded data
block retry limit (analog loopback answer mode)
1203 - xx Modem External
Termination Test
1203 - 01 Modem external
TIP/RING failure
1203 - 02 Modem external DATA
TIP/RING failure
1203 - 03 Modem line termination
failure
1204 - xx Modem Auto Originate
Test
1205 - xx Modem Auto Answer
Test
----------------------------------------------------------------------------­Error Recommended Code Description Action
----------------------------------------------------------------------------­1206 - xx Dial Multifrequency Tone The following steps apply
Test to error codes 1201 - xx
through 1210 - xx:
1210 - xx Modem Direct Connect 1. Refer to modem
Test documentation for
Configuration utility
1210 - 01 Modem timed out waiting procedures.
for SYNC 2. Check the modem line.
3. Replace the modem
1210 - 02 Modem timed out waiting and retest.
for response
1210 - 03 Modem exceeded data
block retry limit
1210 - 04 RCV exceeded carrier
lost limit
1210 - 05 XMIT exceeded carrier
lost limit
1210 - 06 Time out waiting for dial
tone
1210 - 07 Dial number string too
long
Page 36
1210 - 08 Modem timed out waiting
for remote response
1210 - 09 Modem exceeded
maximum redial limit
1210 - 10 Line quality prevented
remote connection
1210 - 11 Modem timed out waiting
for remote connection
1210 - 17 Tone detection failure =============================================================================
Table 3-10. Fixed Disk Drive Test Error Codes ============================================================================= Error Recommended Code Description Action
----------------------------------------------------------------------------­1700 - xx Fixed disk ID drive The following steps apply
types test failed to error codes 1700 - xx
through 1719 - xx:
1701 - xx Fixed disk drive format 1. Replace the fixed disk
test failed drive and retest.
2. Replace the power
1702 - xx Fixed disk drive read distribution
test failed board and retest.
3. Replace the I/O board
1703 - xx Fixed disk drive write and retest.
read compare test failed
1704 - xx Fixed disk drive random
seek test failed
1705 - xx Fixed disk drive
controller test failed
1706 - xx Fixed disk drive ready
test failed
1707 - xx Fixed disk drive recalibrate
test failed
1708 - xx Fixed disk drive format bad
track test failed
1709 - xx Fixed disk drive reset
controller test failed
1710 - xx Fixed disk drive park head
test failed
----------------------------------------------------------------------------­Error Recommended Code Description Action
----------------------------------------------------------------------------­1714 - xx Fixed disk drive file The following steps apply
write test failed to error codes 1700 - xx
through 1719 - xx:
1715 - xx Fixed disk drive head 1. Replace the fixed disk
Page 37
select test failed drive and retest.
2. Replace the power
1716 - xx Fixed disk drive conditional distribution board and
format test failed retest.
3. Replace the I/O board
1717 - xx Fixed disk drive Error Correction and retest.
Code test failed
1719 - xx Fixed disk drive power
mode test
1719 - 01 Exceeded maximum soft
error limit
1719 - 02 Exceeded maximum hard
error limit
1719 - 03 Previously exceeded
maximum soft error limit
1719 - 04 Previously exceeded
maximum hard error limit
1719 - 05 Failed to reset controller
1719 - 06 Fatal error while reading
1719 - 07 Fatal error while writing
----------------------------------------------------------------------------­Error Recommended Code Description Action
----------------------------------------------------------------------------­1719 - 08 Failed compare of The following steps apply
write/read/compare to error codes 1700 - xx
through 1719 - xx:
1719 - 09 Failed to format a track 1. Replace the fixed disk
drive and retest.
1719 - 10 Failed sector wrap test 2. Replace the power
distribution board
1719 - 19 Controller failed to and retest.
deallocate bad sector 3. Replace the I/O board
and retest.
1719 - 40 Failed cylinder 0
1719 - 41 Drive not ready
1719 - 42 Recalibrate failed
1719 - 43 Failed to format bad
track
1719 - 44 Failed fixed disk drive
controller diagnostics
1719 - 45 Failed to get drive
parameters from ROM
1719 - 46 Invalid drive parameters
found in ROM
Page 38
1719 - 47 Failed to park heads
1719 - 48 Failed to move disk
table to RAM
----------------------------------------------------------------------------­Error Recommended Code Description Action
----------------------------------------------------------------------------­1719 - 49 Failed to read media in The following steps apply
file write test to error codes 1700 - xx
through 1719 - xx:
1719 - 50 Failed file I/O write test 1. Replace the fixed disk
drive and retest.
1719 - 51 Failed file I/O read test 2. Replace the power
distribution board
1719 - 52 Failed file I/O compare test and retest.
3. Replace the I/O board
1719 - 53 Failed drive/head and retest.
register test
1719 - 54 Failed digital input
register test
1719 - 55 Failed cylinder 1
1719 - 56 Fixed disk drive controller
RAM diagnostics failed
1719 - 57 Fixed disk drive
controller to drive test failed
1719 - 58 Failed to write sector
buffer
1719 - 59 Failed to read sector
buffer
1719 - 60 Failed to compare sector
buffer
1719 - 61 Failed uncorrectable
Error Correction Code error
----------------------------------------------------------------------------­Error Recommended Code Description Action
----------------------------------------------------------------------------­1719 - 62 Failed correctable Error The following steps apply
Correction Code error to error codes 1700 - xx
through 1719 - xx:
1719 - 63 Failed soft error rate 1. Replace the fixed disk
and retest.
1719 - 65 Exceeded maximum 2. Replace the power
bad sector per track distribution board
and retest.
1719 - 66 Failed initial drive 3. Replace the I/O board
parameter and retest.
1719 - 67 Failed to write long
Page 39
1719 - 68 Failed to read long
1719 - 69 Failed to read drive size
from controller
1719 - 70 Failed translate mode
1719 - 71 Failed nontranslated mode
1719 - 72 Bad track limit exceeded
1719 - 73 Previously exceeded bad
track limit
1719 - 74 Failed sleep mode
1719 - 75 Failed idle mode
1719 - 76 Failed standby mode
1719 - 77 Failed to change mode
1719 - 78 Exceeded spinup time limit =============================================================================
----------------------------------------------------------------------------­1900 - xx Tape ID failed The following steps
apply to error codes
1901 - xx Tape servo write failed 1901 - xx through
1906 - xx:
1902 - xx Tape format failed 1. Replace the tape
cartridge and retest.
1903 - xx Tape drive sensor test 2. Replace the tape drive
failed and retest.
3. Replace the I/O board
1904 - xx Tape BOT/EOT test failed and retest.
1905 - xx Tape read test failed
1906 - xx Tape write/read/compare
test failed
1906 - 01 Drive not installed
1906 - 02 Cartridge not installed
1906 - 03 Tape motion error
1906 - 04 Drive busy error
1906 - 05 Track seek error
1906 - 06 Tape write protected error
1906 - 07 Tape already servo written
Page 40
1906 - 08 Unable to servo write
----------------------------------------------------------------------------­Error Recommended Code Description Action
----------------------------------------------------------------------------­1906 - 09 Unable to format The following steps apply
to error codes 1901 - xx
1906 - 10 Format mode error through 1906 - xx:
1. Replace the tape
1906 - 11 Drive recalibration error cartridge and retest.
2. Replace the tape
1906 - 12 Tape not servo written drive and retest.
3. Replace the I/O board
1906 - 13 Tape not formatted and retest.
1906 - 14 Drive timeout error
1906 - 15 Sensor error flag
1906 - 16 Block locate (block ID)
error
1906 - 17 Soft error limit exceeded
1906 - 18 Hard error limit exceeded
1906 - 19 Write (probably ID) error
1906 - 20 NEC fatal error
1906 - 21 Received servo pulses
second time but not first
1906 - 22 Never got to EOT after
servo check
----------------------------------------------------------------------------­Error Recommended Code Description Action
----------------------------------------------------------------------------­1906 - 23 Change line not set The following steps apply
to error codes 1901 - xx
1906 - 24 Write protect error through 1906 - xx:
1. Replace the tape
1906 - 25 Unable to erase cartridge cartridge and retest.
2. Replace the tape
1906 - 26 Cannot identify drive drive and retest.
3. Replace the I/O board
1906 - 27 Drive not compatible with and retest.
controller
1906 - 28 Format gap error
1906 - 30 Exception bit not set
1906 - 31 Unexpected drive status
1906 - 32 Device fault
1906 - 33 Illegal command
Page 41
1906 - 34 No data detected
1906 - 35 Power on reset occurred
1906 - 91 Power lost during test =============================================================================
Table 3-12. Video Test Error Codes ============================================================================= Error Recommended Code Description Action
----------------------------------------------------------------------------­2402 - 01 Video memory test failed Replace the video board
and retest for error
2403 - 01 Video attribute test failed codes 2402 - xx through
2432 - xx.
2404 - 01 Video character set test
failed
2405 - 01 Video 80 x 25 mode
9 x 14 character cell test failed
2406 - 01 Video 80 x 25 mode8x8
character cell test failed
2407 - 01 Video 40 x 25 mode test
failed
2408 - 01 Video 320 x 200 mode
color set 0 test failed
2409 - 01 Video 320 x 200 mode
color set 1 test failed
2410 - 01 Video 640 x 200 mode
test failed
2411 - 01 Video screen memory
page test failed
2412 - 01 Video gray scale test failed
2414 - 01 Video white screen test
failed
----------------------------------------------------------------------------­Error Recommended Code Description Action
----------------------------------------------------------------------------­2416 - 01 Video noise pattern test Replace the video board
failed and retest for error codes
2402 - xx through
2418 - 01 Video memory test failed 2432 - xx.
2418 - 02 Video shadow RAM test
failed
2419 - 01 Video ROM checksum
test failed
Page 42
2420 - 01 Video attribute test failed
2421 - 01 Video 640 x 200 graphics
mode test failed
2422 - 01 Video 640 x 350 16
color set test failed
2423 - 01 Video 640 x 350 64
color set test failed
2424 - 01 Video monochrome text
mode test failed
2425 - 01 Video monochrome
graphics mode test failed
2431 - xx Video 640 x 480 graphics
mode test failed
2432 - xx Video 320 x 200 graphics
mode test failed
=============================================================================
Table 3-13. Pointing Device Interface Test Error Codes ============================================================================= Error Recommended Code Description Action
----------------------------------------------------------------------------­8601 - xx Pointing Device Interface 1. Install new copy of
test failed mouse driver software.
2. Replace with a working pointing device and retest.
3. Replace the I/O board and retest.
=============================================================================
Chapter 3.3 Memory Error Codes
Memory error codes appear when the system detects a memory fault during the Power On Self Test (201 or 203 error codes) or as a result of a diagnostic test. The TEST programs attempt to isolate the memory fault to a specific location, then generate a memory error code.
The memory error code points to a specific memory address. The physical location of the memory address depends on the number and type of memory modules installed and the type of memory device used.
Memory error codes are displayed in an eight digit format (XX000Y ZZ). The XX and Y alphanumeric codes are key identification points for defective memory isolation.
XX000Y ZZ Error Message | | | | |-------- 201 (ROM) |||| | | | --------------------- Failed data bit. Values are: 00, 01, 02, 04,
Page 43
| | | 08, 10, 20, 40, 80, ?? ||| | | | 00 = parity bit | | | 01 = data bit 0 | | | 02 = data bit 1 | | | 04 = data bit 2 | | | 08 = data bit 3 | | | 10 = data bit 4 | | | 20 = data bit 5 | | | 40 = data bit 6 | | | 80 = data bit 7 | | | ?? = unable to determine failed data bit. ||| | | ------------------------ Failed byte. Values are 0, 1. || | -------------------------- Always 000. |
----------------------------- Failed address. Values are 00 through 20.
0X = error in 1st megabyte 1X = error in 2nd megabyte 2X = error in 3rd megabyte 3X = error in 4th megabyte
Page 44
Chapter 4. Illustrated Parts Catalog
This chapter provides an illustrated parts breakdown and identifies the spare parts for the standard features of the COMPAQ PORTABLE 486c Personal Computer.
Chapter 4.1 Illustrated Parts Breakdown
System Unit
Page 45
Table 4-1. System Unit ============================================================================= Description Spare Part Number
-----------------------------------------------------------------------------
1. System Chassis 128937-001
2. Front Bezel 128946-001
3. Rear Panel 128938-001 Handle Connector Cover Enhanced Option Cover
4. Base Panel 128948-001
5. Tilt Base 135999-001
6. Power Supply 128898-001
7. Fan Assembly 128901-001
8. Keylock 135901-001
9. AC Power Cord (U.S./Canada) 121258-001
(UK) 128943-001 *
-----------------------------------------------------------------------------
* Not shown
=============================================================================
Active Matrix Color Display
Table 4-2. Active Matrix Color Display
Page 46
============================================================================= Description Spare Part Number
-----------------------------------------------------------------------------
1. Front Bezel 128946-001
2. Display Assembly 128902-001
Display Shield
3. Backlight Assembly 136964-001
Display Shield
4. Video Cable 128903-001
5. Display Inverter Board 128900-001
=============================================================================
Mass Storage Devices
Table 4-3. Mass Storage Devices ============================================================================= Description Spare Part Number
-----------------------------------------------------------------------------
1. 210 Megabyte Fixed Disk Drive 128956-001
2. 120 Megabyte Fixed Disk Drive 128955-001
3. 3 1/2 inch 1.44 Megabyte
Diskette Drive 123313-001
=============================================================================
Cables
Page 47
Table 4-4. Cables ============================================================================= Description Spare Part Number
-----------------------------------------------------------------------------
1. Power Distribution Board 128935-001
2. Video Cable 128903-001
=============================================================================
Processor Board
Page 48
Table 4-5. COMPAQ PORTABLE 486c Personal Computer Processor Board Connectors =============================================================================
1. Memory Module Connectors, Slots 2, 3, and 4
2. Intel 486 33 MHz Microprocessor Connector
3. System ROM Connector
4. Real Time Clock/Battery Connector
5. Memory Module Connector, Slot 1
=============================================================================
I/O Board
Table 4-6. COMPAQ PORTABLE 486c Personal Computer I/O Board Connectors =============================================================================
1. Enhanced Option Connector
2. Internal Keyboard Connector
3. Fan Assembly Connector
4. Diskette Drive Connector
5. Fixed Disk Drive Connector
6. Processor Slot
7. Video Slot
8. Audio Input Jack
9. EISA Slots
10. I/O Board Switches
11. Serial Connector
12. Parallel Connector
13. External Storage Module Connector
14. CD-ROM Connector
15. Pointing Device (Mouse) Connector
16. External Keyboard Connector
=============================================================================
Standard Boards
Page 49
Table 4-7. Processor and Standard Board Assemblies and Subassemblies ============================================================================= Item Description Spare Part Number
-----------------------------------------------------------------------------
1. Processor Board 128897-001
2. 4 Megabyte Memory Module 118741-001
3. System ROM 128939-001
4. Real Time Clock/Battery 126570-001
5. I/O Board 128949-001
6. Video Board 128899-001
7. Display Inverter Board 128900-001
8. Speaker Assembly 128966-001
=============================================================================
Keyboard
Page 50
Table 4-8. Keyboards ============================================================================= Description Spare Part Number
-----------------------------------------------------------------------------
1. U.S. English 128958-001
2. Keyboard template 128934-001
3. UK English 128958-003 *
4. German 128958-004 *
5. French 128958-005 *
6. Italian 128958-006 *
7. Spanish 128958-007 *
8. Danish 128958-008 *
9. Norwegian 128958-009 *
10. Swedish/Finnish 128958-010 *
11. Swiss 128958-011 *
12. Portuguese 128958-013 *
13. Latin American 128958-016 *
14. Belgian 128958-018 *
-----------------------------------------------------------------------------
* Not shown
=============================================================================
Chapter 4.2 Spare Part Numbers
The following table provides a list of all of the spare part descriptions and part numbers for standard features of the COMPAQ PORTABLE 486c Personal Computer. Refer to the OPTIONS AND PERIPHERALS MAINTENANCE AND SERVICE GUIDE for spare part numbers to optional features.
Table 4-9. Spare Parts List ============================================================================= Description Part Number
Page 51
-----------------------------------------------------------------------------
System Unit:
System Chassis 128937-001 Front Bezel 128946-001 Rear Panel 128938-001
Handle Connector Cover
Enhanced Option Cover Base Panel 128948-001 Tilt Base 135999-001 Power Supply 128898-001 Fan Assembly 128901-001 Keylock 135901-001 AC Power Cord (U.S./Canada) 121258-001 AC Power Cord (UK) 128943-001
Active Matrix Color Display:
Front Bezel 128946-001 Display Assembly 128902-001 Display Shield Backlight Assembly 136964-001 Display Shield Video Cable 128903-001 Display Inverter Board 128900-001
Mass Storage Devices:
210 Megabyte Fixed Disk Drive 128956-001 120 Megabyte Fixed Disk Drive 128955-001 3 1/2 inch 1.44 Megabyte Diskette Drive 123313-001
Cables:
Power Distribution Board 128935-001 Video Cable 128903-001
Processor and Standard Board Assemblies and Subassemblies:
Processor Board 128897-001 4 Megabyte Memory Module 118741-001 System ROM 128939-001 Real Time Clock/Battery 126570-001 I/O Board 128949-001 Video Board 128899-001 Display Inverter Board 128900-001 Speaker Assembly 128966-001
Keyboards:
U.S. English 128958-001 Keyboard template 128934-001 UK English 128958-003 German 128958-004 French 128958-005 Italian 128958-006 Spanish 128958-007 Danish 128958-008 Norwegian 128958-009 Swedish/Finnish 128958-010 Swiss 128958-011 Portuguese 128958-013 Latin American 128958-016
Page 52
Belgian 128958-018
Documentation:
Service Aids Kit 105264-001 Maintenance and Service Guides:
COMPAQ PORTABLE 486c Personal Computer 128987-001
Options and Peripherals Volume 1 120577-001
Options and Peripherals Volume 2 120577-001
Options and Peripherals Volume 3 120577-001
Support Software 120576-001 Operations Guide 128940-001 COMPAQ PORTABLE 486c
PERSONAL COMPUTER TECHNICAL
REFERENCE GUIDE 128822-001 COMPAQ SERVICE QUICK REFERENCE
GUIDE 106854-001 Diagnostics
3 1/2 inch 720 Kbyte Diskette * User Programs
3 1/2 inch 1.44 Megabyte Diskette *
----------------------------------------------------------------------------­* The software spare part numbers are subject to change. Please consult the
current price list for the software spare part number before ordering.
=============================================================================
Table 4-10. Miscellaneous Hardware ============================================================================= Description Part Number
----------------------------------------------------------------------------­Logo Labels 128944-001
Plastic Parts Kit 135900-001
Access Cover Brightness/Volume Controls Board Guide Assembly Keyboard Feet Options Door Options Bezel Screw Covers Switch Cover
Hardware Kit 128945-001
Anti skid feet Backlight cable Diskette drive cage ground strap Display inverter board insulator Fixed disk drive ground strap Enhanced option cap Enhanced option shield Options cover
Screw Kit 133982-001
4-40 x 3/16, PNHD, Torx
Screw Kit 136965-001
6-19 x 1/4, PNHD, Torx, PT, CS
Screw Kit 136973-001
6-19 x 1/2, PNHD, Torx, Plastite
Page 53
Screw Kit 136967-001
6-32, MA, TH, T-15, CS
Screw Kit 119548-001
6-32 x 1/4, Torx, TT, HI, T/WSr
Screw Kit 136966-001
6-32 x 1/4, S-Torx, PNHD
Screw Kit 128212-001
6-32 x 1/4, TAPTITE, HT
Screw Kit 136974-001
6-32 x 1/2, S-Torx, TT
=============================================================================
Page 54
Chapter 5. Removal and Replacement Procedures
Introduction
This chapter provides module level removal and replacement procedures for the COMPAQ PORTABLE 486c Personal Computer.
After completing all removal and replacement procedures, run the Diagnostics program to verify that all components operate properly. Refer to the SUPPORT SOFTWARE MAINTENANCE AND SERVICE GUIDE for information on installing new or updated utilities when adding or removing options.
Chapter 5.1 Electrostatic Discharge
Before beginning to remove and replace a component in the COMPAQ PORTABLE 486c Personal Computer, be sure you are discharged of static electricity.
A sudden discharge of static electricity from a finger or other conductor can destroy static sensitive devices or micro circuitry. Often the spark is neither felt nor heard, but damage occurs. An electronic device exposed to electrostatic discharge (ESD) may not be affected at all and will work perfectly throughout a normal cycle. Or it may function normally for awhile, then degrade in the internal layers, reducing its life expectancy.
Networks built into many integrated circuits provide some protection, but in many cases, the discharge contains enough power to alter device parameters and/or melt silicon junctions.
Generating Static
Table 5-1 shows how different methods generate static electricity and at different electrostatic voltage levels.
Table 5-1. Typical Electrostatic Voltages ============================================================================= Event Relative Humidity
----------------------------------------------------------------------------­Walking across carpet 35,000V 15,000V 7,500V Walking across vinyl floor 12,000V 5,000V 3,000V Motions of bench worker 6,000V 800V 400V Removing DIPs from plastic tubes 2,000V 700V 400V Removing DIPs from vinyl trays 11,500V 4,000V 2,000V Removing DIPs from Styrofoam 14,500V 5,000V 3,500V Removing bubble pack from PCBs 26,000V 20,000V 7,000V Packing PCBs in foam lined box 21,000V 11,000V 5,000V =============================================================================
10% 40% 55%
NOTE: 700 volts can degrade a product.
Preventing Electrostatic Damage to Equipment
Many electronic components are sensitive to ESD. Circuitry design and structure determine the degree of sensitivity. Proper packaging and
Page 55
grounding are necessary precautions to prevent damage. Use the following precautions to protect equipment from static damage:
o To avoid hand contact, transport products in static safe containers such as
tubes, bags, or boxes.
o Protect all electrostatic parts and assemblies by conductive or approved
containers or packaging.
o Keep electrostatic sensitive parts in their containers until they arrive at
static free stations.
o Place items on a grounded surface before removing them from their
container.
o Always be properly grounded when touching a sensitive component or
assembly.
o Place reusable electrostatic sensitive parts from assemblies in protective
packaging or conductive foam.
Use transporters and conveyors made of antistatic belts and metal roller bushings. Mechanized equipment used for moving materials must be wired to ground and proper materials selected to minimize static charging. When grounding is not possible, use an ionizer to dissipate electric charges.
Preventing Damage to Drives
To prevent static damage to diskette drives and fixed disk drives, handle drives gently and perform the following static guarding techniques:
o Store drives in their original shipping containers. o Avoid dropping the drive from any height onto any surface. o Handle drives on surfaces which have at least one inch of shock proof foam. o Always place drives PCB assembly side down on the foam.
Grounding Methods
Methods for grounding must include either a wrist strap or a foot strap at a grounded workstation. When seated, wear a wrist strap connected to a grounded system. When standing, use footstraps and a grounded floor mat.
Table 5-2 lists different antistatic materials and their shielding protection levels.
Table 5-2. Static Shielding Protection Levels ================================================== Method Voltages
-------------------------------------------------­Antistatic plastic 1,500 Carbon loaded plastic 7,500 Metallized laminate 15,000 ==================================================
Page 56
Grounding Workstations
To provide a grounded workstation, do the following:
o Cover workstations with approved static dissipating material. Provide a
wrist strap connected to work surface and properly grounded tools and equipment.
o Use static dissipating mats, heel straps, or air ionizers to give added
protection.
o Handle electrostatic sensitive components, parts, and assemblies by the
case or PCB laminate. Handle them only at static free workstations.
o Avoid contact with pins, leads, or circuitry.
o Turn off power and input signals before inserting and removing connectors
or test equipment to the computer.
o Use fixtures made of static safe materials when fixtures must directly
contact dissipating surfaces.
o Keep work area free of non conductive materials such as ordinary plastic
assembly aids and Styrofoam.
o Use field service tools, such as cutters, screwdrivers, vacuums, that are
conductive.
o Use a portable field service kit with a static dissipating vinyl pouch that
folds out to a work mat. Also use a wrist strap and a ground cord for the work surface. Ground the cord to the chassis of the equipment undergoing test or repair.
Grounding Equipment
Use the following equipment to prevent static electricity damage to equipment:
Wrist Straps are flexible straps with a minimum of 1 megohm ñ 10% resistance in the ground cords. To provide proper ground, a strap must be worn snug against the skin. On grounded mats without banana plug connectors, connect a wrist strap with alligator clips.
Heelstraps/Toestraps/Bootstraps can be used at standing workstations and are compatible with most types of shoes or boots. On conductive floors or dissipative floor mats, use them on both feet with a minimum of 1 megohm resistance between operator and ground. To be effective the conductive strips must be worn in contact with the skin.
Other materials and equipment that are recommended for use in preventing static electricity include:
o Antistatic tape
o Antistatic smocks, aprons or sleeve protectors
o Conductive bins and other assembly or soldering aids
Page 57
o Conductive foam
o Conductive table top workstations with ground cord of 1 megohm resistance
o Static dissipating table or floor mats with hard tie to ground
o Field service kits
o Static awareness labels
o Wrist straps and footwear straps providing 1 megohm ñ 10% resistance
o Material handling packages
- Conductive plastic bags
- Conductive plastic tubes
- Conductive tote boxes
- Metal tote boxes
- Opaque shielding bags
- Transparent metallized shielding bag
- Transparent shielding tubes
Chapter 5.2 Tool and Software Requirements
To service the COMPAQ PORTABLE 486c Personal Computer, you need the following:
o Case utility tool o Flathead screwdriver o Modem terminating plug o Nonconductive probe o ROM removal tool o Torx screwdrivers, sizes T-10 and T-15 o 9 pin serial interface loopback plug o 25 pin parallel interface loopback plug
Chapter 5.3 Disassembly/Assembly Sequence Chart
Use the following chart as a reference along with the procedures in this chapter for removing and replacing the subassemblies of the COMPAQ PORTABLE 486c Personal Computer.
5.4 PREPARATION PROCEDURES |
5.5 |-- KEYBOARD |
5.6 |-- REAR PANEL ||
5.7 | |-- OPTIONS COVER ||
5.8 | |-- STANDARD BOARDS | | |-- Video Board | | |-- Processor Board | | |-- System ROM
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| | |-- Real Time Clock/Battery ||
5.9 | |-- POWER SUPPLY ||
5.10 | |-- FAN ASSEMBLY ||
5.11 | |-- I/O BOARD |
5.12 |-- BASE PANEL |
5.13 |-- MASS STORAGE DEVICES | |-- Diskette Drive | |-- Fixed Disk Drive |
5.14 |-- ACTIVE MATRIX COLOR DISPLAY | |-- Front Bezel | |-- Display Assembly | |-- Backlight Assembly | |-- Display Inverter Board | |-- Speaker Assembly |
5.15 |-- POWER DISTRIBUTION BOARD |
5.16 |-- KEYLOCK
Chapter 5.4 Preparation Procedures
Before beginning the removal and replacement procedures, complete the following steps:
1. Turn off the computer.
2. Disconnect the AC power cord from the AC outlet and from the computer
(Figure 5-1).
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3. Disconnect all external devices (printer, monitor, and other devices)
from the computer.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>><<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
CAUTION
Static electricity can damage the CMOS components. Be sure that you are properly grounded before performing any of the following procedures.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>><<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
CAUTION
Screws in this system are not interchangeable. As you remove screws, place them with the component you removed. Damage may occur if you insert these screws in the wrong place.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>><<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
Chapter 5.5 Keyboard
To remove the keyboard, complete the following steps:
1. Remove the keyboard from storage position by pressing down on the two
keyboard latches and pulling the keyboard out from the front bezel (Figure 5-2).
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2. Using a nonconductive probe, remove the access cover (Figure 5-3).
3. Disconnect the keyboard cable by gently pulling the keyboard connector
tab (Figure 5-4).
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4. Carefully remove the keyboard cable from the cable slot (Figure 5-4).
To replace the keyboard, reverse the steps in the above illustrations.
Chapter 5.6 Rear Panel
To remove the rear panel, complete the following steps:
1. Push the tilt adjustment buttons on the sides of the computer in and tilt
the display assembly forward (Figure 5-5).
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2. Lift the handle and remove two screws, using a Torx T-15 screwdriver
(Figure 5-5).
3. Pull the rear panel out and up, until the bottom latches are released
from the slots (Figure 5-6).
To replace the rear panel, complete the following steps:
1. Position the rear panel on the computer by aligning the bottom latches
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with the appropriate slots.
2. Slide the rear panel down and forward, and secure with the two screws
using a Torx T-15 screwdriver.
Chapter 5.7 Options Cover
To remove the options cover, complete the following steps:
2. Using a Torx T-15 screwdriver, remove three screws from the top of the
options cover (Figure 5-7).
3. Loosen two slotted screws (Figure 5-8).
4. Lift the options cover off of the slotted screws (Figure 5-8).
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To replace the options cover, reverse the steps in the above illustration.
Chapter 5.8 Standard Boards
Video Board
To remove the video board, complete the following steps:
2. Remove the options cover (Section 5.7).
3. Remove any expansion boards from the expansion slots (Refer to the COMPAQ
PORTABLE 486c Personal Computer Reference Guide).
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>><<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
When removing or inserting cables with Zero Insertion Force (ZIF) connectors, do not pull, twist, or apply tension to cables.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>><<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
CAUTION
NOTE: The ZIF connectors in this product have mechanical latches that either slide foreword and lift up or slide up to open. Be sure the latches on the ZIF connectors are opened before attempting to remove the cable.
4. Carefully disconnect the video board cable from the ZIF connector
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(Figure 5-9).
5. Carefully disconnect the video cable from the video board (Figure 5-9).
6. Using a Torx T-10 screwdriver, remove the screw securing the video board
(Figure 5-9).
7. Carefully pull the video board out of the slot (Figure 5-9).
To replace the video board, reverse the steps in the above illustration.
Processor Board
To remove the processor board, complete the following steps:
2. Remove the options cover (Section 5.7).
3. Remove the video board (Section 5.8).
4. Using a Torx T-15 screwdriver, remove five screws securing the processor
board to the display pan (Figure 5-10).
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5. Carefully pull the processor board out of the slot (Figure 5-10).
To replace the processor board, reverse the steps in the above illustration.
System ROM
To remove the system ROM from the processor board, complete the following steps:
2. Remove the options cover (Section 5.7).
3. Remove the video board (Section 5.8).
4. Remove the processor board.
5. Locate the system ROM on the processor board (Figure 5-11).
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6. Using the ROM removal tool, grasp the ROM and gently pull up until it is
released from the socket (Figure 5-11).
To replace the system ROM, reverse the steps in the above illustration.
NOTE: When replacing the system ROM, align Pin 1 with the dot on the system ROM socket.
Real Time Clock/Battery
To remove the real time clock/battery, complete the following steps:
2. Remove the options cover (Section 5.7).
3. Remove the video board (Section 5.8).
4. Remove the processor board (Section 5.8).
5. Locate the real time clock/battery on the processor board (Figure 5-12).
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>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>><<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
WARNING
The real time clock/battery contains a lithium battery that may explode if mishandled. Do not abuse, recharge, disassemble, or dispose of in fire.
Use only replacement real time clock/battery modules supplied by Compaq Computer Corporation (part no. 126570-001).
Disposal of the real time clock/battery should be accomplished within compliance of local regulations or returned to Compaq Computer Corporation by established parts return methods.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>><<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
6. Cut the tie wrap securing the real time clock/battery to the processor
board and remove the real time clock/battery (Figure 5-12).
To replace the real time clock/battery, reverse the steps in the above illustration.
Chapter 5.9 Power Supply
To remove the power supply, complete the following steps:
2. Remove the options cover (Section 5.7).
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3. Using a Torx T-15 screwdriver, remove three screws securing the power
supply to the I/O board (Figure 5-13).
4. Pull out the power supply with the switch bezel attached (Figure 5-13).
5. Remove the switch bezel from the power supply (Figure 5-13).
To replace the power supply, reverse the steps in the above illustration.
Chapter 5.10 Fan Assembly
To remove the fan assembly, complete the following steps:
2. Remove the options cover (Section 5.7).
3. Carefully disconnect the fan assembly cable (Figure 5-14).
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4. Using a Torx T-10 screwdriver, remove the screw securing the fan assembly
(Figure 5-14).
5. Slide the fan assembly out (Figure 5-14).
To replace the fan assembly, reverse the steps in the above illustration.
Chapter 5.11 I/O Board
To remove the I/O board, complete the following steps:
2. Remove the options cover (Section 5.7).
3. Remove the video board (Section 5.8).
4. Remove the processor board (Section 5.8).
5. Remove the power supply (Section 5.9).
6. Remove the fan assembly (Section 5.10).
7. Carefully disconnect the diskette drive cable, fixed disk drive cable,
and power cable (Figure 5-15).
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8. Disconnect the fan assembly cable (Figure 5-15).
9. Using a Torx T-10 screwdriver, remove the screw securing the internal
keyboard connector to the display pan (Figure 5-15).
10. Using a Torx T-15 screwdriver, remove seven screws securing the I/O
board (Figure 5-15).
To replace the I/O board, reverse the steps in the above illustration.
Chapter 5.12 Base Panel
To remove the base panel, complete the following steps:
IMPORTANT: The base panel cannot be removed with the cable lock provision pulled out. Be sure the cable lock provision is completely pushed in before performing the following steps.
1. Push in the cable lock provision (Figure 5-16).
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2. Position the computer on the rear panel (Figure 5-16).
3. Using a Torx T-15 screwdriver, remove the screw from the base panel
(Figure 5-16).
4. Remove the base panel by sliding it out toward the diskette drive side of
the computer (Figure 5-16).
To replace the base panel, reverse the steps in the above illustration.
Chapter 5.13 Mass Storage Devices
Diskette Drive
To remove the diskette drive, complete the following steps:
1. Remove the base panel (Section 5.12).
2. Carefully disconnect the cable from the diskette drive (Figure 5-17).
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3. Using a Torx T-15 screwdriver, remove the screws securing the diskette
drive cage; then swing the drive cage out (Figure 5-17).
4. Using a Torx T-15 screwdriver, remove four screws securing the diskette
drive to the drive cage (Figure 5-17).
To replace the diskette drive, reverse the steps in the above illustration.
Fixed Disk Drive
To remove the fixed disk drive, complete the following steps:
1. Remove the base panel (Section 5.12).
2. Carefully disconnect the two cables from the fixed disk drive
(Figure 5-18).
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3. Using a Torx T-15 screwdriver, remove the screws securing the fixed disk
drive cage; then swing the drive cage out (Figure 5-18).
4. Lift the fixed disk drive out of the cage and remove the shock mounts
(Figure 5-19).
To replace the fixed disk drive, reverse the steps in the above illustrations.
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Chapter 5.14 Active Matrix Color Display
Front Bezel
To remove the front bezel, complete the following steps:
1. Remove the keyboard (Section 5.5).
2. Pull the brightness and volume controls off (Figure 5-20).
3. Remove four plastic screw covers from the front bezel (Figure 5-20).
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>><<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
WARNING
The display inverter board contains high voltage. Avoid contact with all surfaces of the display inverter board when removing the front bezel.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>><<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
4. Using a Torx T-15 screwdriver, remove four Plastite screws securing the
front bezel (Figure 5-20).
5. Pull the front bezel out from the display assembly (Figure 5-20).
To replace the front bezel, reverse the steps in the above illustration.
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Display Assembly
To remove the display assembly, complete the following steps:
1. Remove the keyboard (Section 5.5).
2. Remove the front bezel (Section 5.14).
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>><<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
WARNING
The display inverter board contains High Voltage. Avoid contact with all surfaces of the display inverter board when removing the display assembly.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>><<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
CAUTION
Before touching the display assembly, be sure you are discharged of static electricity by touching a grounded metal object.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>><<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
3. Using a Torx T-15 screwdriver, remove four screws securing the display
assembly (Figure 5-21).
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>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>><<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
CAUTION
When removing or inserting cables with ZIF connectors, do not pull, twist, or apply tension to cables.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>><<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
NOTE: The ZIF connectors in this product have mechanical latches that either slide forward and lift up or slide up to open. Be sure the latches on the ZIF connectors are opened before attempting to remove the cable.
4. Carefully disconnect the video board cable from the ZIF connector
(Figure 5-21).
5. Carefully disconnect two display inverter board cables (Figure 5-21).
6. Remove the display assembly and the display shield (Figure 5-21).
To replace the display assembly, reverse the steps in the above illustrations.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>><<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
CAUTION
Do not clean the display screen with soap or isopropyl alcohol. Gently wipe the display screen with a clean, low lint cloth, moistened with water.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>><<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
Backlight Assembly
To remove the backlight assembly, complete the following steps:
1. Remove the keyboard (Section 5.5).
2. Remove the front bezel (Section 5.14).
3. Remove the display assembly (Section 5.14).
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>><<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
Before touching the display assembly, be sure you are discharged of static electricity by touching a grounded metal object.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>><<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
CAUTION
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4. Place the display assembly screen down on a soft, clean surface.
5. Using a Phillips screwdriver, remove the four screws securing the display
assembly to the backlight assembly (Figure 5-22).
6. Carefully release the display assembly cables from the four corner
brackets (Figure 5-22).
7. Release the five tabs securing the backlight assembly to the display
assembly (Figure 5-22).
To replace the backlight assembly, reverse the steps in the above illustration.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>><<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
CAUTION
When installing the display assembly cables into the four corner brackets, ensure that the cable wires are not pulled, twisted, or pinched.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>><<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
NOTE: When replacing the backlight assembly, align the five tabs with the display assembly.
Display Inverter Board
To remove the display inverter board, complete the following steps:
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1. Remove the keyboard (Section 5.5).
2. Remove the front bezel (Section 5.14).
3. Remove the display assembly (Section 5.14).
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>><<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
WARNING
The display inverter board contains high voltage. Avoid contact with all surfaces of the board.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>><<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
CAUTION
When removing or inserting cables with ZIF connectors, do not pull, twist, or apply tension to cables.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>><<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
NOTE: The ZIF connectors in this product have mechanical latches that either slide forward and lift up or slide up to open. Be sure the latches on the ZIF connectors are opened before attempting to remove the cable.
4. Carefully disconnect the power distribution board cable from the ZIF
connector on the display inverter board (Figure 5-23).
5. Carefully disconnect two cables from the display assembly (Figure 5-23).
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6. Pull the display inverter board insulator aside to gain access to the
screws (Figure 5-23).
7. Using a Torx T-15 screwdriver, remove five screws securing the display
inverter board (Figure 5-23).
To replace the display inverter board, reverse the steps in the above illustration.
Speaker Assembly
To remove the speaker assembly from the display inverter board, complete the following steps:
1. Remove the keyboard (Section 5.5).
2. Remove the front bezel (Section 5.14).
3. Carefully disconnect the speaker assembly cable from the display inverter
board (Figure 5-24).
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4. Carefully release the speaker assembly tabs and remove the speaker
assembly from the display inverter board (Figure 5-24).
To replace the speaker assembly, reverse the steps in the above illustration.
Chapter 5.15 Power Distribution Board
To remove the power distribution board, complete the following steps:
1. Remove the keyboard (Section 5.5).
2. Remove the front bezel (Section 5.14).
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>><<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
When removing or inserting cables with ZIF connectors, do not pull, twist, or apply tension to cables.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>><<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
NOTE: The ZIF connectors in this product have mechanical latches that either slide forward and lift up or slide up to open. Be sure the latches on the ZIF connectors are opened before attempting to remove the cable.
CAUTION
3. Carefully disconnect the power distribution cable from the ZIF connector
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on the display inverter board (Figure 5-25).
4. Turn the computer around and remove the rear panel (Section 5.6).
5. Remove the options cover (Section 5.7).
6. Remove the video board (Section 5.8).
7. Remove the processor board (Section 5.8).
8. Remove the power supply (Section 5.9).
9. Remove the fan assembly (Section 5.10).
10. Remove the I/O board (Section 5.11).
11. Remove the base panel (Section 5.12).
12. Carefully disconnect the diskette drive cable, fixed disk drive cable,
and power cable (Figure 5-26).
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13. Using a Torx T-15 screwdriver, remove four screws securing the power
distribution board (Figure 5-27).
14. Carefully pull the I/O cables, diskette drive cable, fixed disk drive
cable, and power cable through their respective slots and remove the power distribution board (Figure 5-27).
To replace the power distribution board, reverse the steps in the above illustrations.
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Chapter 5.16 Keylock
To remove the keylock, complete the following steps:
2. Remove the options cover (Section 5.7).
3. Using a flathead screwdriver, remove the metal clip securing the keylock
(Figure 5-28).
4. Pull the keylock out of the computer (Figure 5-28).
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To replace the keylock, reverse the steps in the above illustration.
Chapter 5.17 Memory Expansion
Some of the memory expansion alternatives for the COMPAQ PORTABLE 486c Personal Computer are shown in Table 5-3. Memory modules can be added in combinations of 2, 4, and 8 megabytes for a total of 32 megabytes.
NOTE: Memory modules can be installed in any combination and in any available slot. However, slot 1 must contain a memory module.
Table 5-3. Memory Expansion COMPAQ PORTABLE 486c Personal Computer =============================================================================
Memory Module(s) Added Total
Slot 1 to Slots 2, 3, or 4 Memory
-----------------------------------------------------------------------------
4MB 2MB 2MB 6MB 4MB 2MB 2MB 2MB 8MB 4MB 4MB 2MB 8MB 4 MB 2 MB 2 MB 2 MB 10 MB 4 MB 2 MB 4 MB 2 MB 10 MB 4 MB 2 MB 2 MB 4 MB 12 MB 4 MB 4 MB 4 MB 2 MB 12 MB 4MB 8MB 2MB 12MB 4 MB 2 MB 4 MB 4 MB 14 MB 4 MB 2 MB 8 MB 2 MB 14 MB 4 MB 2 MB 2 MB 8 MB 16 MB 4 MB 4 MB 4 MB 4 MB 16 MB 4 MB 4 MB 8 MB 2 MB 16 MB 4 MB 2 MB 4 MB 8 MB 18 MB 4 MB 4 MB 4 MB 8 MB 20 MB 4 MB 8 MB 8 MB 2 MB 20 MB
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4 MB 2 MB 8 MB 8 MB 22 MB 4 MB 4 MB 8 MB 8 MB 24 MB 4 MB 8 MB 8 MB 8 MB 28 MB
||| | |
||| | | 8 MB 8 MB 8 MB 8 MB 32 MB =============================================================================
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Chapter 6. Jumper and Switch Information
This chapter provides the switch settings for the COMPAQ PORTABLE 486c Personal Computer I/O board. The I/O board contains six switches. The default settings shown in the following table are set for the computer as configured by Compaq Computer Corporation. These settings need to be changed only when the system configuration changes.
Table 6-1 lists the switch settings and describes the function of each switch. Figure 6-1 shows the location of the switches on the I/O board.
Table 6-1. I/O Board Switch Settings (Assy No. 002142) ============================================================================= Switch Position Status Function
----------------------------------------------------------------------------­SW1 ON Disabled Controls the integrated
OFF Enabled video graphics controller.
OFF is the default position.
ON is used to avoid conflict when using a third party video board.
----------------------------------------------------------------------------­SW2 ON Enabled Controls EISA configuration.
OFF Disabled
OFF is the default position and allows the user to change the configuration in CMOS.
ON allows the EISA configuration to be viewed but not changed.
----------------------------------------------------------------------------­SW3 ON Enabled Controls Read/Write
OFF Disabled to the Diskette Drive.
OFF is the default position and allows Read/Write capability.
ON sets the diskette drive for Read only.
----------------------------------------------------------------------------­Switch Position Status Function
----------------------------------------------------------------------------­SW4 ON Enabled Controls whether the diskette
OFF Disabled can be used to restart.
OFF is the default position and uses the EISA configuration selection.
ON allows the user to restart from the diskette drive and overrides the EISA configuration selection.
-----------------------------------------------------------------------------
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SW5 ON Enabled Controls the power on
OFF Disabled password.
OFF is the default position and enables the power on password feature.
ON will clear the power on password.
----------------------------------------------------------------------------­SW6 ON Enabled Allows the configuration
OFF Disabled memory to be cleared.
OFF is the default position and allows configuration memory to remain unchanged.
ON clears the configuration memory.
=============================================================================
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