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Dell Latitude C840 Service Manual Dell™ Latitude™ C840 Service Manual Before You Begin Preparing to Work Inside the Computer Recommended Tools Computer Orientation Screw Identification System Components Hard Drive and Fixed Optical Drive ... System Board Battery and Module Bay Latches Battery Charger Board LED Board Fan RJ-11/RJ-45 Module Pin Assignments for I/O Connectors file:///F|/Service%20Manuals/Dell/Latitude/c840/index.htm (1 of 2) [2/28/2004 8:03:26 AM]
Dell Latitude C840 Service Manual Dell™ Latitude™ C840 Service Manual Before You Begin Preparing to Work Inside the Computer Recommended Tools Computer Orientation Screw Identification System Components Hard Drive and Fixed Optical Drive ... System Board Battery and Module Bay Latches Battery Charger Board LED Board Fan RJ-11/RJ-45 Module Pin Assignments for I/O Connectors file:///F|/Service%20Manuals/Dell/Latitude/c840/index.htm (1 of 2) [2/28/2004 8:03:26 AM]
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...AM] Save any work surface is undocked. 5. file:///F|/Service%20Manuals/Dell/Latitude/c840/begin working inside the computer. 1. Before You Begin: Dell Latitude C840 Service Manual Back to Contents Page Before You Begin Dell™ Latitude™ C840 Service Manual Preparing to Work Inside the Computer Recommended Tools Computer ...in "Safety and EMC Instructions: Portable Computers" in progress and exit all attached devices. Ensure that is not authorized by Dell is not in a power-management mode. 4. Damage due to prevent scratching the computer cover. 2. Turn off the computer...
...AM] Save any work surface is undocked. 5. file:///F|/Service%20Manuals/Dell/Latitude/c840/begin working inside the computer. 1. Before You Begin: Dell Latitude C840 Service Manual Back to Contents Page Before You Begin Dell™ Latitude™ C840 Service Manual Preparing to Work Inside the Computer Recommended Tools Computer ...in "Safety and EMC Instructions: Portable Computers" in progress and exit all attached devices. Ensure that is not authorized by Dell is not in a power-management mode. 4. Damage due to prevent scratching the computer cover. 2. Turn off the computer...
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... Tools The procedures in the module bay. 12. To avoid possible damage to the system board, wait 10 to upgrade the BIOS) file:///F|/Service%20Manuals/Dell/Latitude/c840/begin.htm (2 of 6) [2/28/2004 8:03:35 AM] Before You Begin...
... Tools The procedures in the module bay. 12. To avoid possible damage to the system board, wait 10 to upgrade the BIOS) file:///F|/Service%20Manuals/Dell/Latitude/c840/begin.htm (2 of 6) [2/28/2004 8:03:35 AM] Before You Begin...
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The placemat provides the number of the component screws. Before You Begin: Dell Latitude C840 Service Manual Computer Orientation Screw Identification When you are removing and replacing components, photocopy the placemat as a tool to lay out and keep track of screws and the sizes. Screw Identification file:///F|/Service%20Manuals/Dell/Latitude/c840/begin.htm (3 of 6) [2/28/2004 8:03:35 AM]
The placemat provides the number of the component screws. Before You Begin: Dell Latitude C840 Service Manual Computer Orientation Screw Identification When you are removing and replacing components, photocopy the placemat as a tool to lay out and keep track of screws and the sizes. Screw Identification file:///F|/Service%20Manuals/Dell/Latitude/c840/begin.htm (3 of 6) [2/28/2004 8:03:35 AM]
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... Mounting Bracket to Bottom Case: M2.5 x 20 mm (4 each ) Keyboard to Top Cover: file:///F|/Service%20Manuals/Dell/Latitude/c840/begin.htm (4 of the correct diameter and length. Hard-Drive Door Security: M3 x 5 mm (1 each ; Before You Begin: Dell Latitude C840 Service Manual NOTICE: When reinstalling a screw, you must use a screw of 6) [2/28/2004 8:03:35 AM...
... Mounting Bracket to Bottom Case: M2.5 x 20 mm (4 each ) Keyboard to Top Cover: file:///F|/Service%20Manuals/Dell/Latitude/c840/begin.htm (4 of the correct diameter and length. Hard-Drive Door Security: M3 x 5 mm (1 each ; Before You Begin: Dell Latitude C840 Service Manual NOTICE: When reinstalling a screw, you must use a screw of 6) [2/28/2004 8:03:35 AM...
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Before You Begin: Dell Latitude C840 Service Manual M2.5 x 4 mm (1 each) Palm Rest to Bottom Case: M2.5 x 20 mm (9 each) System Board: M2.5 x 4 mm captive washer (3 each) LED Board: M2 x 4 mm (2 each) Palm Rest Bracket: M2.5 x 4 mm (4 each) M2.5 x 20 mm (1 each) Fan: M2 x 4 mm (3 each) Memory Module/Modem Cover: M2.5 x 20 mm (1 each) Modem Daughter Card: M2 x 3 mm (1 each) Mini PCI Card: M2.5 x 20 mm (1 each) Back to Contents Page file:///F|/Service%20Manuals/Dell/Latitude/c840/begin.htm (5 of 6) [2/28/2004 8:03:35 AM]
Before You Begin: Dell Latitude C840 Service Manual M2.5 x 4 mm (1 each) Palm Rest to Bottom Case: M2.5 x 20 mm (9 each) System Board: M2.5 x 4 mm captive washer (3 each) LED Board: M2 x 4 mm (2 each) Palm Rest Bracket: M2.5 x 4 mm (4 each) M2.5 x 20 mm (1 each) Fan: M2 x 4 mm (3 each) Memory Module/Modem Cover: M2.5 x 20 mm (1 each) Modem Daughter Card: M2 x 3 mm (1 each) Mini PCI Card: M2.5 x 20 mm (1 each) Back to Contents Page file:///F|/Service%20Manuals/Dell/Latitude/c840/begin.htm (5 of 6) [2/28/2004 8:03:35 AM]
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System Components: Dell Latitude C840 Service Manual Back to Contents Page System Components Dell™ Latitude™ C840 Service Manual NOTICE: Unless otherwise noted, each procedure in this document assumes that a part can be replaced by performing the removal procedure in reverse order. file:///F|/Service%20Manuals/Dell/Latitude/c840/system.htm (1 of 2) [2/28/2004 8:03:36 AM]
System Components: Dell Latitude C840 Service Manual Back to Contents Page System Components Dell™ Latitude™ C840 Service Manual NOTICE: Unless otherwise noted, each procedure in this document assumes that a part can be replaced by performing the removal procedure in reverse order. file:///F|/Service%20Manuals/Dell/Latitude/c840/system.htm (1 of 2) [2/28/2004 8:03:36 AM]
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System Components: Dell Latitude C840 Service Manual 1 display assembly 2 hinge cover 3 microprocessor thermalcooling assembly 4 system board 5 hard drive 6 bottom case 7 main battery 8 device in module bay 9 fixed optical drive 10 palm rest 11 keyboard Back to Contents Page file:///F|/Service%20Manuals/Dell/Latitude/c840/system.htm (2 of 2) [2/28/2004 8:03:36 AM]
System Components: Dell Latitude C840 Service Manual 1 display assembly 2 hinge cover 3 microprocessor thermalcooling assembly 4 system board 5 hard drive 6 bottom case 7 main battery 8 device in module bay 9 fixed optical drive 10 palm rest 11 keyboard Back to Contents Page file:///F|/Service%20Manuals/Dell/Latitude/c840/system.htm (2 of 2) [2/28/2004 8:03:36 AM]
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Hard Drive and Fixed Optical Drive: Dell Latitude C840 Service Manual Back to servicing that is not authorized by Dell is very sensitive to shock. Damage due to Contents Page Hard Drive and Fixed Optical Drive Dell™ Latitude™ C840 Service Manual Hard Drive Fixed Optical Drive NOTICE:... by your computer. NOTICE: The hard drive is not covered by periodically touching unpainted metal on your warranty. file:///F|/Service%20Manuals/Dell/Latitude/c840/hdd.htm (1 of the case), and avoid dropping it. Hard Drive NOTICE: Disconnect the computer and attached devices from the...
Hard Drive and Fixed Optical Drive: Dell Latitude C840 Service Manual Back to servicing that is not authorized by Dell is very sensitive to shock. Damage due to Contents Page Hard Drive and Fixed Optical Drive Dell™ Latitude™ C840 Service Manual Hard Drive Fixed Optical Drive NOTICE:... by your computer. NOTICE: The hard drive is not covered by periodically touching unpainted metal on your warranty. file:///F|/Service%20Manuals/Dell/Latitude/c840/hdd.htm (1 of the case), and avoid dropping it. Hard Drive NOTICE: Disconnect the computer and attached devices from the...
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Follow the instructions in "Preparing to Work Inside the Computer." 2. Pull the hard drive out. file:///F|/Service%20Manuals/Dell/Latitude/c840/hdd.htm (2 of computer 2 M3 x 5-mm screw 3 hard drive door Removing the Hard Drive 1. Replacing the Hard Drive 1. Push the hard drive into the drive bay until the drive door is flush with the computer case. Hard Drive and Fixed Optical Drive: Dell Latitude C840 Service Manual 1 bottom of 4) [2/28/2004 8:03:36 AM] Remove the M3 x 5-mm screw. 3.
Follow the instructions in "Preparing to Work Inside the Computer." 2. Pull the hard drive out. file:///F|/Service%20Manuals/Dell/Latitude/c840/hdd.htm (2 of computer 2 M3 x 5-mm screw 3 hard drive door Removing the Hard Drive 1. Replacing the Hard Drive 1. Push the hard drive into the drive bay until the drive door is flush with the computer case. Hard Drive and Fixed Optical Drive: Dell Latitude C840 Service Manual 1 bottom of 4) [2/28/2004 8:03:36 AM] Remove the M3 x 5-mm screw. 3.
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NOTICE: To avoid ESD, ground yourself by using a wrist grounding strap or by periodically touching unpainted metal on the drive until it snaps into place. 3. Hard Drive and Fixed Optical Drive: Dell Latitude C840 Service Manual 2. Replace the M3 x 5-mm screw in the hard drive door. Fixed Optical Drive NOTICE: Disconnect the computer and attached devices from the electrical outlet and remove any installed batteries. Push down on the computer. 1 captive screw 2 pull tab file:///F|/Service%20Manuals/Dell/Latitude/c840/hdd.htm (3 of 4) [2/28/2004 8:03:36 AM]
NOTICE: To avoid ESD, ground yourself by using a wrist grounding strap or by periodically touching unpainted metal on the drive until it snaps into place. 3. Hard Drive and Fixed Optical Drive: Dell Latitude C840 Service Manual 2. Replace the M3 x 5-mm screw in the hard drive door. Fixed Optical Drive NOTICE: Disconnect the computer and attached devices from the electrical outlet and remove any installed batteries. Push down on the computer. 1 captive screw 2 pull tab file:///F|/Service%20Manuals/Dell/Latitude/c840/hdd.htm (3 of 4) [2/28/2004 8:03:36 AM]
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Back to keep the captive screw from interfering with the pull tab) and pull out the pull tab. 4. Turn the computer over (to Contents Page file:///F|/Service%20Manuals/Dell/Latitude/c840/hdd.htm (4 of the computer. 3. Follow the instructions in "Preparing to remove the fixed optical drive. Use the pull tab to Work Inside the Computer." 2. Hard Drive and Fixed Optical Drive: Dell Latitude C840 Service Manual Removing the Fixed Optical Drive 1. Loosen the captive screw on the bottom of 4) [2/28/2004 8:03:36 AM]
Back to keep the captive screw from interfering with the pull tab) and pull out the pull tab. 4. Turn the computer over (to Contents Page file:///F|/Service%20Manuals/Dell/Latitude/c840/hdd.htm (4 of the computer. 3. Follow the instructions in "Preparing to remove the fixed optical drive. Use the pull tab to Work Inside the Computer." 2. Hard Drive and Fixed Optical Drive: Dell Latitude C840 Service Manual Removing the Fixed Optical Drive 1. Loosen the captive screw on the bottom of 4) [2/28/2004 8:03:36 AM]
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System Upgrades: Dell Latitude C840 Service Manual Back to Contents Page System Upgrades Dell™ Latitude™ C840 Service Manual Memory Modules Modem Daughter Card Mini PCI Card Memory Modules NOTICE: Disconnect the computer and any attached devices from electrical outlets and remove any installed batteries. Removing the Memory Module/Modem Cover file:///F|/Service%20Manuals/Dell/Latitude/c840/upgrades.htm (1 of 9) [2/28/2004 8:03:38 AM] NOTICE: To avoid ESD, ground yourself by using a wrist grounding strap or by periodically touching unpainted metal on the computer.
System Upgrades: Dell Latitude C840 Service Manual Back to Contents Page System Upgrades Dell™ Latitude™ C840 Service Manual Memory Modules Modem Daughter Card Mini PCI Card Memory Modules NOTICE: Disconnect the computer and any attached devices from electrical outlets and remove any installed batteries. Removing the Memory Module/Modem Cover file:///F|/Service%20Manuals/Dell/Latitude/c840/upgrades.htm (1 of 9) [2/28/2004 8:03:38 AM] NOTICE: To avoid ESD, ground yourself by using a wrist grounding strap or by periodically touching unpainted metal on the computer.
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Follow the instructions in "Preparing to Work Inside the Computer." 2. Remove the M2.5 x 20-mm screw from the memory module/modem cover. 3. System Upgrades: Dell Latitude C840 Service Manual 1 M2.5 x 20-mm screw 1. Disengage the metal tabs at the opposite end of 9) [2/28/2004 8:03:38 AM] file:///F|/Service%20Manuals/Dell/Latitude/c840/upgrades.htm (2 of the cover.
Follow the instructions in "Preparing to Work Inside the Computer." 2. Remove the M2.5 x 20-mm screw from the memory module/modem cover. 3. System Upgrades: Dell Latitude C840 Service Manual 1 M2.5 x 20-mm screw 1. Disengage the metal tabs at the opposite end of 9) [2/28/2004 8:03:38 AM] file:///F|/Service%20Manuals/Dell/Latitude/c840/upgrades.htm (2 of the cover.
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Lift the memory module out of its socket, spread apart the tabs at each side of 9) [2/28/2004 8:03:38 AM] To release a memory module from its socket. file:///F|/Service%20Manuals/Dell/Latitude/c840/upgrades.htm (3 of the module until the module pops up slightly. 3. Remove the memory module/modem cover. 2. System Upgrades: Dell Latitude C840 Service Manual 1 DIMM B 2 memory module sockets (2) 3 DIMM A socket 4 modem daughter card 5 metal tabs (2 per socket) Removing the Memory Modules 1.
Lift the memory module out of its socket, spread apart the tabs at each side of 9) [2/28/2004 8:03:38 AM] To release a memory module from its socket. file:///F|/Service%20Manuals/Dell/Latitude/c840/upgrades.htm (3 of the module until the module pops up slightly. 3. Remove the memory module/modem cover. 2. System Upgrades: Dell Latitude C840 Service Manual 1 DIMM B 2 memory module sockets (2) 3 DIMM A socket 4 modem daughter card 5 metal tabs (2 per socket) Removing the Memory Modules 1.
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... Daughter Card NOTICE: Disconnect the computer and any attached devices from electrical outlets and remove any installed batteries. file:///F|/Service%20Manuals/Dell/Latitude/c840/upgrades.htm (4 of 9) [2/28/2004 8:03:38 AM] Install a second memory module in "Preparing to fit into the...the M2.5 x 20-mm screw. If you only have one direction. 2. Insert the metal tabs on the computer. 1. System Upgrades: Dell Latitude C840 Service Manual Replacing the Memory Modules 1. NOTE: Memory modules are keyed to Work Inside the Computer." 2. Follow the instructions in the socket...
... Daughter Card NOTICE: Disconnect the computer and any attached devices from electrical outlets and remove any installed batteries. file:///F|/Service%20Manuals/Dell/Latitude/c840/upgrades.htm (4 of 9) [2/28/2004 8:03:38 AM] Install a second memory module in "Preparing to fit into the...the M2.5 x 20-mm screw. If you only have one direction. 2. Insert the metal tabs on the computer. 1. System Upgrades: Dell Latitude C840 Service Manual Replacing the Memory Modules 1. NOTE: Memory modules are keyed to Work Inside the Computer." 2. Follow the instructions in the socket...
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....htm (5 of the cable to pull the modem daughter card straight up out of its connector. System Upgrades: Dell Latitude C840 Service Manual 1 modem daughter card 2 M2 x 3-mm screw 3. Pull the connector on the modem cable. Remove the M2 x 3-mm screw that secures the modem daughter ...
....htm (5 of the cable to pull the modem daughter card straight up out of its connector. System Upgrades: Dell Latitude C840 Service Manual 1 modem daughter card 2 M2 x 3-mm screw 3. Pull the connector on the modem cable. Remove the M2 x 3-mm screw that secures the modem daughter ...
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... and boss holes at opposite corners of the modem daughter card to the internal antenna of 9) [2/28/2004 8:03:38 AM] System Upgrades: Dell Latitude C840 Service Manual 2. Replace the memory module/modem cover. A wireless modem card must remove the optional Mini PCI wireless modem (if installed) before the...: Disconnect the computer and attached devices from electrical outlets and remove any installed batteries. Mini PCI Card Cover file:///F|/Service%20Manuals/Dell/Latitude/c840/upgrades.htm (6 of the computer. Install the M2 x 3-mm screw that secures the card to the system board. 4.
... and boss holes at opposite corners of the modem daughter card to the internal antenna of 9) [2/28/2004 8:03:38 AM] System Upgrades: Dell Latitude C840 Service Manual 2. Replace the memory module/modem cover. A wireless modem card must remove the optional Mini PCI wireless modem (if installed) before the...: Disconnect the computer and attached devices from electrical outlets and remove any installed batteries. Mini PCI Card Cover file:///F|/Service%20Manuals/Dell/Latitude/c840/upgrades.htm (6 of the computer. Install the M2 x 3-mm screw that secures the card to the system board. 4.
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... the card and disconnect any attached cables. Follow the instructions in "Preparing to Work Inside the Computer." 2. Replacing the Mini PCI Card 1. file:///F|/Service%20Manuals/Dell/Latitude/c840/upgrades.htm (7 of 9) [2/28/2004 8:03:38 AM] Align the Mini PCI card with the socket at a 45-degree angle, and press the Mini PCI... metal securing tabs until the card pops up slightly. 4. Remove the M2.5 x 20-mm screw and then remove the Mini PCI card cover. 3. System Upgrades: Dell Latitude C840 Service Manual 1 M2.5 x 20-mm screw Removing the Mini PCI Card 1.
... the card and disconnect any attached cables. Follow the instructions in "Preparing to Work Inside the Computer." 2. Replacing the Mini PCI Card 1. file:///F|/Service%20Manuals/Dell/Latitude/c840/upgrades.htm (7 of 9) [2/28/2004 8:03:38 AM] Align the Mini PCI card with the socket at a 45-degree angle, and press the Mini PCI... metal securing tabs until the card pops up slightly. 4. Remove the M2.5 x 20-mm screw and then remove the Mini PCI card cover. 3. System Upgrades: Dell Latitude C840 Service Manual 1 M2.5 x 20-mm screw Removing the Mini PCI Card 1.
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Replace the Mini PCI card cover and the M2.5 x 20-mm screw. file:///F|/Service%20Manuals/Dell/Latitude/c840/upgrades.htm (8 of 9) [2/28/2004 8:03:38 AM] Pivot the Mini PCI card down until it clicks into place. 4. Connect the internal-antenna cable to the primary-antenna connector on card 3. System Upgrades: Dell Latitude C840 Service Manual 2. do not force the connections. 1 internal-antenna cable 2 primary-antenna connector on the card. NOTICE: The connectors are keyed for correct insertion;
Replace the Mini PCI card cover and the M2.5 x 20-mm screw. file:///F|/Service%20Manuals/Dell/Latitude/c840/upgrades.htm (8 of 9) [2/28/2004 8:03:38 AM] Pivot the Mini PCI card down until it clicks into place. 4. Connect the internal-antenna cable to the primary-antenna connector on card 3. System Upgrades: Dell Latitude C840 Service Manual 2. do not force the connections. 1 internal-antenna cable 2 primary-antenna connector on the card. NOTICE: The connectors are keyed for correct insertion;