Toshiba Libretto 50CT/70CT Manual

							4-ivLibretto 50CT/70CT Maintenance ManualFigure 4-13  Five screws removal.....................................................................................4-17
Figure 4-14  Display assembly removal.............................................................................4-18
Figure 4-15  RTC battery removal....................................................................................4-19
Figure 4-16  System board removal..................................................................................4-20
Figure 4-17  Mask seal removal........................................................................................4-21
Figure 4-18  Display mask removal...................................................................................4-22
Figure 4-19  FL inverter board removal............................................................................4-23
Figure 4-20  LCD module removal...................................................................................4-25
Figure 4-21  Power switch board removal.........................................................................4-27
Figure 4-22  Speaker removal...........................................................................................4-28
Figure 4-23  Inserting the speaker fix shaft.......................................................................4-28
Figure 4-24  AccuPoint board removal.............................................................................4-29
Figure 4-25  Flexible cable removal..................................................................................4-31
Figure 4-26  Preforming the LCD flexible cable................................................................4-32
Figure 4-27  Silver screw removal....................................................................................4-33
Figure 4-28  Upper cover removal....................................................................................4-33
Figure 4-29  I/O adapter board removal............................................................................4-34 
						

							4 Replacement Procedures 4.1  OverviewLibretto 50CT/70CT Maintenance Manual4-14 
4.1 Overview
This section explains how to disassemble the computer and replace Field Replaceable Units
(FRUs).  It may not be necessary to remove all the FRUs in order to replace one.  The chart
below is a guide to which FRUs need to be removed in order to remove others.  Always start
by removing the battery pack, then follow the lines on the chart to determine which FRU you
must remove next in order to repair the one you think is causing the computer to operate
improperly. 
						

							4.1  Overview4  Replacement Procedures4-2Libretto 50CT/70CT Maintenance ManualSafety PrecautionsBefore you begin disassembly, read the following safety precautions and observe them
carefully as you work.
DANGER:1.Always use the lithium ion battery pack or backup battery that is authorized by Toshiba or compatible with the unit.  Since other batterypacks have different specifications, they may be incompatible with the unit, andmay burst or explode. Heating or disassembling the battery pack could causeleakage of alkaline solution.  Throwing the battery pack into a fire couldcause the battery pack to explode.2.The power supply, FL inverter and other components carry highvoltages. To avoid the risk of electric shock when you need to turn on thepower of a partially disassembled computer to check its operation, be carefulnot to touch connectors or components. Also, do not disassemble individualcomponents during first-level maintenance.WARNING: To avoid the risk of electric shock or other injury:1.Always turn the power off and disconnect the AC power cord from thepower source.2.Remove any metal jewelry or accessories such as necklaces, bracelets, or rings. Batteries in the computer retain electrical charge so there is danger ofelectrical shock even when the computer is disconnected from an AC powersource.3.Never work with wet or damp hands.4.The computer contains many sharp edges and corners, so be careful not toinjure yourself.5.Make sure that all replacement components meet the specifications for thecomputer and that all cables and connectors are securely fastened.CAUTION:To avoid damage to the computer:1.When you change a component, be sure the replacement componentmeets the required specifications.2.Metal objects such as screws or paper clips which fall into the unit can causeshort-circuit, fire, or other internal damage.3.When assembling the computer make sure you use the correct screws to securethe various pieces in place.  Screw sizes are listed in the corresponding figure.Make sure all screws are securely fastened.  Loose screws can cause shortcircuits, resulting in heat, smoke, or fire.4.Before removing an FRU or other component, make sure all cables to thecomponent have been removed.5.If you use AC power, be sure to use the cable that came with the computeror one recommended by Toshiba. 
						

							4 Replacement Procedures 4.1  OverviewLibretto 50CT/70CT Maintenance Manual4-3Before You BeginLook over the procedures in this section before you begin disassembling the computer.
Familiarize yourself with the disassembly and reassembly steps. Begin each procedure by
removing the AC adapter and the battery pack as instructed in Section 4.2.
1. Do not disassemble the computer unless it is operating abnormally.
2. Use only the correct and approved tools.
3. Make sure the working environment is free from the following elements whether you
are using or storing the computer:
q Dust and contaminates
q Static electricity
q Extreme heat, cold and humidity
4. Make sure the FRU you are replacing is causing the abnormal operation by performing
the necessary diagnostics tests described in this manual.
5. Do not perform any operations that are not necessary and use only the described
procedures for removing and installing FRUs in the computer.
6. After removing parts from the computer, place them in a safe place away from the
computer so they will not be damaged and will not interfere with your work.
7. You will remove and replace many screws when you disassemble the computer.  When
you remove screws, make sure they are put in a safe place and are identified with the
correct parts.
8. When assembling the computer, be sure you use the correct screws to secure the
various pieces in place.  Screw sizes are listed in the corresponding figures.
9. The computer contains many sharp edges and corners, be careful not to injure
yourself.
10. After you have replaced an FRU, be sure the computer is functioning properly by
performing the appropriate test on the FRU you have fixed or replaced. 
						

							4.1  Overview4  Replacement Procedures4-4Libretto 50CT/70CT Maintenance ManualDisassembly ProceduresThere are three basic types of cable connectors.
q Pressure plate connector
q Normal pin connector
q Flexible Cable Connector
To disconnect a Pressure Plate connector, lift up the tabs on either side of the plastic pressure
plate and slide the cable out of the connector. To connect the cable to a Pressure Plate
connector, make sure the pressure plate is fully lifted and slide the cable into the connector.
Secure the cable in place by pushing the sides of the pressure plate down so the plate is flush
with the sides of the connector. Gently pull on the cable to make sure the cable is secure. If
the connector comes out, connect it again making sure the pressure plate is fully lifted when
you insert the cable.
Standard pin and flexible cable connectors are used for all other cables.  The cables can be
connected to and disconnected from these connectors by simply pulling or pushing.
Reassembly ProceduresAfter you have disassembled the computer and fixed or repaired the problem that was causing
the computer to operate abnormally, you will need to reassemble the computer.
While assembling the computer, remember the following general points:
q Take your time, making sure you follow the instructions closely. Most problems arise
when you hurry to assemble the computer.
q Be sure all cables and connectors are securely fastened.
q Before securing the FRU or other parts, be sure that no cables will be pinched by
screws or the FRU.
q Check that all latches are closed securely in place.
q Be sure the correct screws are used to secure all FRUs. Using the wrong screw can
damage the threads on the screw or the head of the screw and may prevent proper
seating of an FRU.
After installing an FRU in the computer confirm that the FRU and the computer are
functioning properly. 
						

							4 Replacement Procedures 4.1  OverviewLibretto 50CT/70CT Maintenance Manual4-5Tools and Equipment
The use of Electrostatic Discharge (ESD) equipment is very important for your safety and the
safety of those around you. Proper use of these devices will increase the success rate of your
repairs and lower the cost for damaged or destroyed parts. The following equipment is
necessary to disassemble and reassemble the computer:
q One M2 Phillips screwdriver to remove and replace screws.
q Tweezers, to lift out screws that you cannot grasp with your fingers.
q ESD mats for the floor and the table you are working on.
q An ESD wrist strap or heel grounder.
q Antistatic carpeting or flooring.
q Air ionizers in highly static sensitive areas.
q Plastic card the size of a credit card.
Screw Tightening Torques
When you fasten screws, be sure to follow the torque list below. Overtightening can damage
components and screws; undertightening can result in electrical shorts or other damage if
screws or components come loose.
q M20.22 N•m (2.2 kgf•cm)
q M2.50.36 N•m (3.5 kgf•cm)
q FDD (External)0.22 N•m (2.2 kgf•cm)
q HDD0.3   N•m (3.1 kgf•cm) or less
q M30.49 N•m (5.0 kgf cm)
q Thin-head M2.5 0.22 N•m (2.2 kgf.cm) 
						

							4.2  Battery Pack4  Replacement Procedures4-6Libretto 50CT/70CT Maintenance Manual4.2 Battery PackRemoving the Battery Pack
To remove the battery pack, follow the steps below and refer to Figure 4-1.1. Turn the computer off.  Disconnect the AC adapter and other optional units from the
computer.
2. Turn the computer upside down.
3. Slide the battery release latch to the left to unlock it.
4. With the battery facing up, slide it out.Figure 4-1  Removing the battery pack
NOTE
:  For environmental reasons, do not throw away a spent battery pack.Please return spent battery packs to your Toshiba dealer. 
						

							4 Replacement Procedures 4.2  Battery PackLibretto 50CT/70CT Maintenance Manual4-7Installing the Battery Pack
To install the battery pack, follow the steps below and refer to Figure 4-1.WARNING:  The battery is a lithium ion battery.  The battery can explode if not properlyreplaced, used, handled, or disposed of.  Use only batteries recommended by Toshiba asreplacements.NOTE:  Check the battery terminals visually. If they are dirty, wipe them clean with a drycloth.1. Turn the computer off.  Disconnect the AC adapter and all the external cables from the
computer.
2. Hold the battery in line with the guide rail.
3. Push the battery into position and close the cover. 
						

							4.3  Optional PC Card4  Replacement Procedures4-8Libretto 50CT/70CT Maintenance Manual4.3 Optional PC CardRemoving the Optional PC Card
To remove the optional PC card, be sure the computer is in boot mode.  Follow the steps
below and refer to Figure 4-2.1. Turn the computer off.
2. Slide the PC card release lever to the right.
3. The PC card comes out slightly.  Hold it securely and pull it out.Figure 4-2  Removing the PC Card
NOTE:  The unit may contain a dummy card which is inserted or removed in thesame manner as a normal PC card. 
						

							4 Replacement Procedures 4.3  Optional PC CardLibretto 50CT/70CT Maintenance Manual4-9Installing the Optional PC Card
To install the optional PC card, follow the steps below and refer to Figures 4-3 and 4-2.NOTE:  Before installing the PC card, be sure that the computer is in boot mode.1. Turn the computer off.
2. Insert the PC card.  Carefully push it into place.Figure 4-3  Installing the PC card
3. Visually check that, when the PC card is fully inserted, the PC card release lever is
positioned on the left.
NOTE:  The unit may contain a dummy card which is inserted or removed in thesame manner as a normal PC card.