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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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... flat and clean to prevent scratching the computer cover. 2. Disconnect the computer from the electrical outlet. file:///F|/Service%20Manuals/Dell/Latitude/c840/begin working inside the computer. 1. Read and follow all safety instructions in "Safety and EMC Instructions: Portable Computers" ...2004 8:03:35 AM] Save any work surface is undocked. 5. 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 Orientation Screw Identification Preparing ...
... flat and clean to prevent scratching the computer cover. 2. Disconnect the computer from the electrical outlet. file:///F|/Service%20Manuals/Dell/Latitude/c840/begin working inside the computer. 1. Read and follow all safety instructions in "Safety and EMC Instructions: Portable Computers" ...2004 8:03:35 AM] Save any work surface is undocked. 5. 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 Orientation Screw Identification Preparing ...
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...turn the computer upside down on a flat work , periodically touch an unpainted metal surface on the computer chassis. 13. Before You Begin: Dell Latitude C840 Service Manual 6. To avoid possible damage to the system board, wait 10 to 20 seconds and then disconnect any device installed in this document... extractor q Nonmarring plastic scribe q Flash BIOS update floppy disk or CD (provided when needed to upgrade the BIOS) file:///F|/Service%20Manuals/Dell/Latitude/c840/begin.htm (2 of 6) [2/28/2004 8:03:35 AM] Handle components and cards by their edges, and avoid touching pins and contacts.
...turn the computer upside down on a flat work , periodically touch an unpainted metal surface on the computer chassis. 13. Before You Begin: Dell Latitude C840 Service Manual 6. To avoid possible damage to the system board, wait 10 to 20 seconds and then disconnect any device installed in this document... extractor q Nonmarring plastic scribe q Flash BIOS update floppy disk or CD (provided when needed to upgrade the BIOS) file:///F|/Service%20Manuals/Dell/Latitude/c840/begin.htm (2 of 6) [2/28/2004 8:03:35 AM] Handle components and cards by their edges, and avoid touching pins and contacts.
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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 6) [2/28/2004 8:03:35 AM] Screw Identification file:///F|/Service%20Manuals/Dell/Latitude/c840/begin.htm (3 of the component screws. The placemat provides the number of screws and the sizes.
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 6) [2/28/2004 8:03:35 AM] Screw Identification file:///F|/Service%20Manuals/Dell/Latitude/c840/begin.htm (3 of the component screws. The placemat provides the number of screws and the sizes.
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... Graphics Board: M2.5 x 8 (3 each) M2.5 x 4 mm (6 each) Flex-Cable 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. Ensure that the screw is properly aligned with its corresponding hole, and avoid overtightening. Hard-Drive Door...
... Graphics Board: M2.5 x 8 (3 each) M2.5 x 4 mm (6 each) Flex-Cable 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. Ensure that the screw is properly aligned with its corresponding hole, and avoid overtightening. Hard-Drive Door...
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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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... on your warranty. NOTICE: The hard drive is very sensitive to servicing that is not authorized by Dell is not covered by your computer. file:///F|/Service%20Manuals/Dell/Latitude/c840/hdd.htm (1 of the case), and avoid dropping it. Damage due to shock. NOTICE: To avoid...the top of 4) [2/28/2004 8:03:36 AM] Hard Drive and Fixed Optical Drive: Dell Latitude C840 Service Manual Back to Contents Page Hard Drive and Fixed Optical Drive Dell™ Latitude™ C840 Service Manual Hard Drive Fixed Optical Drive NOTICE: Only a certified service technician should perform repairs on...
... on your warranty. NOTICE: The hard drive is very sensitive to servicing that is not authorized by Dell is not covered by your computer. file:///F|/Service%20Manuals/Dell/Latitude/c840/hdd.htm (1 of the case), and avoid dropping it. Damage due to shock. NOTICE: To avoid...the top of 4) [2/28/2004 8:03:36 AM] Hard Drive and Fixed Optical Drive: Dell Latitude C840 Service Manual Back to Contents Page Hard Drive and Fixed Optical Drive Dell™ Latitude™ C840 Service Manual Hard Drive Fixed Optical Drive NOTICE: Only a certified service technician should perform repairs on...
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Pull the hard drive out. Replacing the Hard Drive 1. Follow the instructions in "Preparing to Work Inside the Computer." 2. 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] 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. Remove the M3 x 5-mm screw. 3.
Pull the hard drive out. Replacing the Hard Drive 1. Follow the instructions in "Preparing to Work Inside the Computer." 2. 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] 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. Remove the M3 x 5-mm screw. 3.
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Replace the M3 x 5-mm screw in the hard drive door. 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. 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] Fixed Optical Drive NOTICE: Disconnect the computer and attached devices from the electrical outlet and remove any installed batteries. Hard Drive and Fixed Optical Drive: Dell Latitude C840 Service Manual 2.
Replace the M3 x 5-mm screw in the hard drive door. 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. 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] Fixed Optical Drive NOTICE: Disconnect the computer and attached devices from the electrical outlet and remove any installed batteries. Hard Drive and Fixed Optical Drive: Dell Latitude C840 Service Manual 2.
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Turn the computer over (to remove the fixed optical drive. Use the pull tab to keep the captive screw from interfering with the pull tab) and pull out the pull tab. 4. Hard Drive and Fixed Optical Drive: Dell Latitude C840 Service Manual Removing the Fixed Optical Drive 1. Follow the instructions in "Preparing to Contents Page file:///F|/Service%20Manuals/Dell/Latitude/c840/hdd.htm (4 of the computer. 3. Loosen the captive screw on the bottom of 4) [2/28/2004 8:03:36 AM] Back to Work Inside the Computer." 2.
Turn the computer over (to remove the fixed optical drive. Use the pull tab to keep the captive screw from interfering with the pull tab) and pull out the pull tab. 4. Hard Drive and Fixed Optical Drive: Dell Latitude C840 Service Manual Removing the Fixed Optical Drive 1. Follow the instructions in "Preparing to Contents Page file:///F|/Service%20Manuals/Dell/Latitude/c840/hdd.htm (4 of the computer. 3. Loosen the captive screw on the bottom of 4) [2/28/2004 8:03:36 AM] Back to Work Inside the Computer." 2.
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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. NOTICE: To avoid ESD, ground yourself by using a wrist grounding strap or by periodically touching unpainted metal on the computer. 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]
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. NOTICE: To avoid ESD, ground yourself by using a wrist grounding strap or by periodically touching unpainted metal on the computer. 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]
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file:///F|/Service%20Manuals/Dell/Latitude/c840/upgrades.htm (2 of the cover. Disengage the metal tabs at the opposite end of 9) [2/28/2004 8:03:38 AM] System Upgrades: Dell Latitude C840 Service Manual 1 M2.5 x 20-mm screw 1. 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.
file:///F|/Service%20Manuals/Dell/Latitude/c840/upgrades.htm (2 of the cover. Disengage the metal tabs at the opposite end of 9) [2/28/2004 8:03:38 AM] System Upgrades: Dell Latitude C840 Service Manual 1 M2.5 x 20-mm screw 1. 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.
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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. Lift the memory module out of its socket, spread apart the tabs at each side of 9) [2/28/2004 8:03:38 AM] 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. 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. Lift the memory module out of its socket, spread apart the tabs at each side of 9) [2/28/2004 8:03:38 AM] 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. To release a memory module from its socket.
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Follow the instructions in the socket labeled "DIMM B." file:///F|/Service%20Manuals/Dell/Latitude/c840/upgrades.htm (4 of 9) [2/28/2004 8:03:38 AM] Insert the memory-module edge connector into the socket slot at a 45-degree angle and press the ... installed batteries. Turn the computer over and remove the memory module/modem cover. Install a second memory module in "Preparing to fit into place. System Upgrades: Dell Latitude C840 Service Manual Replacing the Memory Modules 1.
Follow the instructions in the socket labeled "DIMM B." file:///F|/Service%20Manuals/Dell/Latitude/c840/upgrades.htm (4 of 9) [2/28/2004 8:03:38 AM] Insert the memory-module edge connector into the socket slot at a 45-degree angle and press the ... installed batteries. Turn the computer over and remove the memory module/modem cover. Install a second memory module in "Preparing to fit into place. System Upgrades: Dell Latitude C840 Service Manual Replacing the Memory Modules 1.
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... modem cable from the modem daughter card. Remove the M2 x 3-mm screw that secures the modem daughter card to the modem daughter card. System Upgrades: Dell Latitude C840 Service Manual 1 modem daughter card 2 M2 x 3-mm screw 3. NOTICE: Do not pull on the end of the cable to pull the modem daughter card straight...
... modem cable from the modem daughter card. Remove the M2 x 3-mm screw that secures the modem daughter card to the modem daughter card. System Upgrades: Dell Latitude C840 Service Manual 1 modem daughter card 2 M2 x 3-mm screw 3. NOTICE: Do not pull on the end of the cable to pull the modem daughter card straight...
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... You must be removed. NOTICE: Disconnect the computer and attached devices from electrical outlets and remove any installed batteries. System Upgrades: Dell Latitude C840 Service Manual 2. Mini PCI Card Cover file:///F|/Service%20Manuals/Dell/Latitude/c840/upgrades.htm (6 of the computer. Replace the memory module/modem cover. NOTICE: To avoid ESD, ground yourself by using a wrist...
... You must be removed. NOTICE: Disconnect the computer and attached devices from electrical outlets and remove any installed batteries. System Upgrades: Dell Latitude C840 Service Manual 2. Mini PCI Card Cover file:///F|/Service%20Manuals/Dell/Latitude/c840/upgrades.htm (6 of the computer. Replace the memory module/modem cover. NOTICE: To avoid ESD, ground yourself by using a wrist...
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..., and press the Mini PCI card into the socket. 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. Lift out the card and disconnect any attached cables. file:///F|/Service%20Manuals...
..., and press the Mini PCI card into the socket. 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. Lift out the card and disconnect any attached cables. file:///F|/Service%20Manuals...
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Pivot the Mini PCI card down until it clicks into place. 4. System Upgrades: Dell Latitude C840 Service Manual 2. NOTICE: The connectors are keyed for correct insertion; file:///F|/Service%20Manuals/Dell/Latitude/c840/upgrades.htm (8 of 9) [2/28/2004 8:03:38 AM] do not force the connections. 1 internal-antenna cable 2 primary-antenna connector on the card. Replace the Mini PCI card cover and the M2.5 x 20-mm screw. Connect the internal-antenna cable to the primary-antenna connector on card 3.
Pivot the Mini PCI card down until it clicks into place. 4. System Upgrades: Dell Latitude C840 Service Manual 2. NOTICE: The connectors are keyed for correct insertion; file:///F|/Service%20Manuals/Dell/Latitude/c840/upgrades.htm (8 of 9) [2/28/2004 8:03:38 AM] do not force the connections. 1 internal-antenna cable 2 primary-antenna connector on the card. Replace the Mini PCI card cover and the M2.5 x 20-mm screw. Connect the internal-antenna cable to the primary-antenna connector on card 3.