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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 Hard Drive Fixed Optical Drive System Upgrades Memory Modules Modem Daughter Card Mini PCI Card Keyboard ... 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 Hard Drive Fixed Optical Drive System Upgrades Memory Modules Modem Daughter Card Mini PCI Card Keyboard ... 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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... inside the computer. 1. Disconnect the computer from the electrical outlet. 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 to Work Inside the Computer CAUTION: Only a certified service technician should perform...
... inside the computer. 1. Disconnect the computer from the electrical outlet. 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 to Work Inside the Computer CAUTION: Only a certified service technician should perform...
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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 screws and the sizes. The placemat provides the number of the component screws. Screw Identification file:///F|/Service%20Manuals/Dell/Latitude/c840/begin.htm (3 of 6) [2/28/2004 8:03:35 AM]
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. The placemat provides the number of the component screws. 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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... Case: M2.5 x 20 mm (4 each ) Flex-Cable Mounting Bracket to Top Cover: file:///F|/Service%20Manuals/Dell/Latitude/c840/begin.htm (4 of 6) [2/28/2004 8:03:35 AM] Before You Begin: Dell Latitude C840 Service Manual NOTICE: When reinstalling a screw, you must use a screw of computer; 1 at display flex-cable strain relief) Display Bezel: Display Panel to Display Mounting Bracket...
... Case: M2.5 x 20 mm (4 each ) Flex-Cable Mounting Bracket to Top Cover: file:///F|/Service%20Manuals/Dell/Latitude/c840/begin.htm (4 of 6) [2/28/2004 8:03:35 AM] Before You Begin: Dell Latitude C840 Service Manual NOTICE: When reinstalling a screw, you must use a screw of computer; 1 at display flex-cable strain relief) Display Bezel: Display Panel to Display Mounting Bracket...
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Follow the instructions in "Preparing to Work Inside the Computer." 2. Hard Drive and Fixed Optical Drive: Dell Latitude C840 Service Manual 1 bottom of 4) [2/28/2004 8:03:36 AM] Replacing the Hard Drive 1. Pull the hard drive out. Push the hard drive into the drive bay until the drive door is flush with the computer case. 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.
Follow the instructions in "Preparing to Work Inside the Computer." 2. Hard Drive and Fixed Optical Drive: Dell Latitude C840 Service Manual 1 bottom of 4) [2/28/2004 8:03:36 AM] Replacing the Hard Drive 1. Pull the hard drive out. Push the hard drive into the drive bay until the drive door is flush with the computer case. 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. 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. 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. 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. 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.
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Turn the computer over (to Work Inside the Computer." 2. Follow the instructions in "Preparing to keep the captive screw from interfering with the pull tab) and pull out the pull tab. 4. Back to remove the fixed optical drive. Loosen the captive screw on the bottom of 4) [2/28/2004 8:03:36 AM] Use the pull tab to Contents Page file:///F|/Service%20Manuals/Dell/Latitude/c840/hdd.htm (4 of the computer. 3. Hard Drive and Fixed Optical Drive: Dell Latitude C840 Service Manual Removing the Fixed Optical Drive 1.
Turn the computer over (to Work Inside the Computer." 2. Follow the instructions in "Preparing to keep the captive screw from interfering with the pull tab) and pull out the pull tab. 4. Back to remove the fixed optical drive. Loosen the captive screw on the bottom of 4) [2/28/2004 8:03:36 AM] Use the pull tab to Contents Page file:///F|/Service%20Manuals/Dell/Latitude/c840/hdd.htm (4 of the computer. 3. Hard Drive and Fixed Optical Drive: Dell Latitude C840 Service Manual Removing the Fixed Optical Drive 1.
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System Upgrades: Dell Latitude C840 Service Manual 1 M2.5 x 20-mm screw 1. Remove the M2.5 x 20-mm screw from the memory module/modem cover. 3. 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.
System Upgrades: Dell Latitude C840 Service Manual 1 M2.5 x 20-mm screw 1. Remove the M2.5 x 20-mm screw from the memory module/modem cover. 3. 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.
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...Modem 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] Insert the memory-module edge connector into the socket slot at... the memory module/modem cover. System Upgrades: Dell Latitude C840 Service Manual Replacing the Memory Modules 1. Install a second memory module in "Preparing to fit into place. Pivot the module down , and replace the M2.5 x 20-mm screw. Follow the instructions in the socket labeled "DIMM...
...Modem 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] Insert the memory-module edge connector into the socket slot at... the memory module/modem cover. System Upgrades: Dell Latitude C840 Service Manual Replacing the Memory Modules 1. Install a second memory module in "Preparing to fit into place. Pivot the module down , and replace the M2.5 x 20-mm screw. Follow the instructions in the socket labeled "DIMM...
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.... Use the pull tab to the system board. 4. Disconnect the modem cable from the modem daughter card. System Upgrades: Dell Latitude C840 Service Manual 1 modem daughter card 2 M2 x 3-mm screw 3. Remove the M2 x 3-mm screw that secures the modem daughter card to pull the modem daughter card straight up out of 9) [2/28/2004 8:03:38...
.... Use the pull tab to the system board. 4. Disconnect the modem cable from the modem daughter card. System Upgrades: Dell Latitude C840 Service Manual 1 modem daughter card 2 M2 x 3-mm screw 3. Remove the M2 x 3-mm screw that secures the modem daughter card to pull the modem daughter card straight up out of 9) [2/28/2004 8:03:38...
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... and attached devices from electrical outlets and remove any installed batteries. Use the screw and boss holes at opposite corners of 9) [2/28/2004 8:03:38 AM] Mini PCI Card Cover file:///F|/Service%20Manuals/Dell/Latitude/c840/upgrades.htm (6 of the modem daughter card to align the card, and ...yourself by using a wrist grounding strap or by periodically touching unpainted metal on the system board. 3. Install the M2 x 3-mm screw that secures the card to the internal antenna of the computer. Replace the memory module/modem cover. System Upgrades: Dell Latitude C840 Service Manual 2.
... and attached devices from electrical outlets and remove any installed batteries. Use the screw and boss holes at opposite corners of 9) [2/28/2004 8:03:38 AM] Mini PCI Card Cover file:///F|/Service%20Manuals/Dell/Latitude/c840/upgrades.htm (6 of the modem daughter card to align the card, and ...yourself by using a wrist grounding strap or by periodically touching unpainted metal on the system board. 3. Install the M2 x 3-mm screw that secures the card to the internal antenna of the computer. Replace the memory module/modem cover. System Upgrades: Dell Latitude C840 Service Manual 2.
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... securing tabs until the card pops up slightly. 4. Disconnect the card from the internal antenna. 5. file:///F|/Service%20Manuals/Dell/Latitude/c840/upgrades.htm (7 of 9) [2/28/2004 8:03:38 AM] System Upgrades: Dell Latitude C840 Service Manual 1 M2.5 x 20-mm screw Removing the Mini PCI Card 1. Follow the instructions in "Preparing to Work Inside the Computer." 2. Replacing the...
... securing tabs until the card pops up slightly. 4. Disconnect the card from the internal antenna. 5. file:///F|/Service%20Manuals/Dell/Latitude/c840/upgrades.htm (7 of 9) [2/28/2004 8:03:38 AM] System Upgrades: Dell Latitude C840 Service Manual 1 M2.5 x 20-mm screw Removing the Mini PCI Card 1. Follow the instructions in "Preparing to Work Inside the Computer." 2. Replacing the...
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Replace the Mini PCI card cover and the M2.5 x 20-mm screw. 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. NOTICE: The connectors are keyed for correct insertion; do not force the connections. 1 internal-antenna cable 2 primary-antenna connector on the card. file:///F|/Service%20Manuals/Dell/Latitude/c840/upgrades.htm (8 of 9) [2/28/2004 8:03:38 AM] System Upgrades: Dell Latitude C840 Service Manual 2.
Replace the Mini PCI card cover and the M2.5 x 20-mm screw. 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. NOTICE: The connectors are keyed for correct insertion; do not force the connections. 1 internal-antenna cable 2 primary-antenna connector on the card. file:///F|/Service%20Manuals/Dell/Latitude/c840/upgrades.htm (8 of 9) [2/28/2004 8:03:38 AM] System Upgrades: Dell Latitude C840 Service Manual 2.
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... labeled "circle K" and one labeled "circle K/M"). 3. Use a nonmarring plastic scribe under the blank key to replace. 4. Keyboard: Dell Latitude C840 Service Manual 1 M2.5 x 20-mm screws (4) Removing the Keyboard 1. file:///F|/Service%20Manuals/Dell/Latitude/c840/keyboard.htm (2 of 5) [2/28/2004 8:03:39 AM] NOTICE: Be careful when handling the keyboard. Follow the instructions in "Preparing to Work...
... labeled "circle K" and one labeled "circle K/M"). 3. Use a nonmarring plastic scribe under the blank key to replace. 4. Keyboard: Dell Latitude C840 Service Manual 1 M2.5 x 20-mm screws (4) Removing the Keyboard 1. file:///F|/Service%20Manuals/Dell/Latitude/c840/keyboard.htm (2 of 5) [2/28/2004 8:03:39 AM] NOTICE: Be careful when handling the keyboard. Follow the instructions in "Preparing to Work...
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..., you replace the keyboard in the bottom case. 2. The keys should be flush with the left end of the keyboard under each screw as you install the screw. Keyboard: Dell Latitude C840 Service Manual NOTICE: Position the keyboard/track-stick flex cable so that the keyboard is not pinched when you can open the computer... bottom case, and fit the keyboard into place. 3. Check that it is correctly installed. Turn the computer over and reinstall the four M2.5 x 20-mm screws.
..., you replace the keyboard in the bottom case. 2. The keys should be flush with the left end of the keyboard under each screw as you install the screw. Keyboard: Dell Latitude C840 Service Manual NOTICE: Position the keyboard/track-stick flex cable so that the keyboard is not pinched when you can open the computer... bottom case, and fit the keyboard into place. 3. Check that it is correctly installed. Turn the computer over and reinstall the four M2.5 x 20-mm screws.
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Display: Dell Latitude C840 Service Manual 1 M2.5 x 6-mm screws (2) 1. NOTICE: Remove the display flex cable before you remove the display assembly. file:///F|/Service%20Manuals/Dell/Latitude/c840/display.htm (4 of 10) [2/28/2004 8:03:40 AM] Remove the hinge cover.
Display: Dell Latitude C840 Service Manual 1 M2.5 x 6-mm screws (2) 1. NOTICE: Remove the display flex cable before you remove the display assembly. file:///F|/Service%20Manuals/Dell/Latitude/c840/display.htm (4 of 10) [2/28/2004 8:03:40 AM] Remove the hinge cover.
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With the display in the middle. Remove the M2.5 x 6-mm flex-cable strain relief screw, and then use the pull loop to the bottom case. 4. file:///F|/Service%20Manuals/Dell/Latitude/c840/display.htm (5 of the connector can damage fragile components. 3. NOTICE: When reconnecting the flex cable, press down on... "circle D" that secure the display assembly to remove the display flex cable from the bottom case. Display: Dell Latitude C840 Service Manual 1 M2.5 x 6-mm screw 2 strain relief 3 display flex cable 4 pull loop 2. Open the display and, from the back of the connector, not in ...
With the display in the middle. Remove the M2.5 x 6-mm flex-cable strain relief screw, and then use the pull loop to the bottom case. 4. file:///F|/Service%20Manuals/Dell/Latitude/c840/display.htm (5 of the connector can damage fragile components. 3. NOTICE: When reconnecting the flex cable, press down on... "circle D" that secure the display assembly to remove the display flex cable from the bottom case. Display: Dell Latitude C840 Service Manual 1 M2.5 x 6-mm screw 2 strain relief 3 display flex cable 4 pull loop 2. Open the display and, from the back of the connector, not in ...
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... located across the top of the bezel. 5. file:///F|/Service%20Manuals/Dell/Latitude/c840/display.htm (7 of the bezel. 2. Display: Dell Latitude C840 Service Manual 1 M2.5 x 4-mm screws (6) 2 rubber screw covers (4) 3 display bezel 4 plastic tabs (6) 5 M2.5 x 4-mm screw 6 flex-cable mounting bracket 7 display latch 8 M2 x 3-mm screws (6) 9 top cover 10 hinge cover 11 display flex cable 12 display panel 13 plastic...
... located across the top of the bezel. 5. file:///F|/Service%20Manuals/Dell/Latitude/c840/display.htm (7 of the bezel. 2. Display: Dell Latitude C840 Service Manual 1 M2.5 x 4-mm screws (6) 2 rubber screw covers (4) 3 display bezel 4 plastic tabs (6) 5 M2.5 x 4-mm screw 6 flex-cable mounting bracket 7 display latch 8 M2 x 3-mm screws (6) 9 top cover 10 hinge cover 11 display flex cable 12 display panel 13 plastic...
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Remove the display bezel. 4. Disconnect the flex cable from the strain relief and the graphics card. 3. Remove the M2.5 x 4-mm screw that secures the plastic flex-cable mounting bracket to the top cover. 5. Detach the display flex cable from the two connectors (one ZIF and one ... the right and left sides of the top cover. 7. Lift the display panel and flex cable out of the panel. 6. Remove the six M2 x 3-mm screws (three on the display panel. file:///F|/Service%20Manuals/Dell/Latitude/c840/display.htm (8 of 10) [2/28/2004 8:03:40 AM] Display...
Remove the display bezel. 4. Disconnect the flex cable from the strain relief and the graphics card. 3. Remove the M2.5 x 4-mm screw that secures the plastic flex-cable mounting bracket to the top cover. 5. Detach the display flex cable from the two connectors (one ZIF and one ... the right and left sides of the top cover. 7. Lift the display panel and flex cable out of the panel. 6. Remove the six M2 x 3-mm screws (three on the display panel. file:///F|/Service%20Manuals/Dell/Latitude/c840/display.htm (8 of 10) [2/28/2004 8:03:40 AM] Display...
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... place and is in the display. 1. Display Latch file:///F|/Service%20Manuals/Dell/Latitude/c840/display.htm (9 of the display panel. 2. Display: Dell Latitude C840 Service Manual 1 ZIF connector 2 standard connector Replacing the Display Panel NOTE: Use a magnetic screwdriver to the top cover. 4. Reinstall the M2.5 x 4-mm screw that the flex cable is not crushed or crimped. 3. Reinstall...
... place and is in the display. 1. Display Latch file:///F|/Service%20Manuals/Dell/Latitude/c840/display.htm (9 of the display panel. 2. Display: Dell Latitude C840 Service Manual 1 ZIF connector 2 standard connector Replacing the Display Panel NOTE: Use a magnetic screwdriver to the top cover. 4. Reinstall the M2.5 x 4-mm screw that the flex cable is not crushed or crimped. 3. Reinstall...