Transporting sensitive components............................ 7 After working inside your computer............................ 7 2 Removing and installing components..................... 8 Recommended tools................................8 Screw list....................................8 Major components of Inspiron 7405 2n1..........................9 Base cover.................................... 10 Removing the base cover..............................10 Installing the base cover..............................13 Battery....................................15 Lithium-ion battery precautions...........................
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Running the SupportAssist Pre-Boot System Performance Check............... 59 System diagnostic lights..............................59 Recovering the operating system............................. 60 Flashing the BIOS.................................61 Flashing BIOS (USB key)..............................61 Backup media and recovery options..........................61 WiFi power cycle.................................. 61 Flea power release................................62 6 Getting help and contacting Dell....................63 Contents...
You should only perform troubleshooting and repairs as authorized or directed by the Dell technical assistance team. Damage due to servicing that is not authorized by Dell is not covered by your warranty. See the safety instructions that is shipped with the product or at www.dell.com/regulatory_compliance.
Due to the increased density of semiconductors used in recent Dell products, the sensitivity to static damage is now higher than in previous Dell products. For this reason, some previously approved methods of handling parts are no longer applicable.
Transporting sensitive components When transporting ESD sensitive components such as replacement parts or parts to be returned to Dell, it is critical to place these parts in anti-static bags for safe transport.
Removing and installing components Recommended tools The procedures in this document may require the following tools: • Phillips screwdrivers #0 and #1 • Plastic scribe Screw list NOTE: When removing screws from a component, it is recommended to note the screw type, the quantity of screws, and then place them in a screw storage box.
Palm-rest and keyboard M2x3 assembly USB Type-C bracket Palm-rest and keyboard M2x3 assembly System board Palm-rest and keyboard M2x2 assembly Major components of Inspiron 7405 2n1 The following image shows the major components of Inspiron 7405 2n1. Removing and installing components...
19. Solid-state drive thermal bracket NOTE: Dell provides a list of components and their part numbers for the original system configuration purchased. These parts are available according to warranty coverages purchased by the customer. Contact your Dell sales representative for purchase options.
Steps 1. Remove the six screws (M2x4) that secure the base cover to the palm-rest and keyboard assembly. 2. Loosen the three captive screws that secure the base cover to the palm-rest and keyboard assembly. NOTE: Upon loosening the three captive screws, the base cover will pop up creating a gap between the base cover and the palm-rest assembly.
If the battery gets stuck inside your computer as a result of swelling, do not try to release it as puncturing, bending, or crushing a lithium-ion battery can be dangerous. In such an instance, contact Dell technical support for assistance. See www.dell.com/contactdell.
Steps 1. Peel the tape that secures the battery cable to the system board (applicable only if not peeled earlier). 2. Disconnect the battery cable from the system board (applicable only if not disconnected earlier). 3. Remove the five screws (M2x3) that secure the battery to the palm-rest and keyboard assembly. 4.
Steps 1. Using the alignment posts, place the battery on the palm-rest and keyboard assembly. 2. Replace the five screws (M2x3) that secure the battery to the palm-rest and keyboard assembly. 3. Connect the battery cable to the system board. 4.
Steps 1. Disconnect the coin-cell battery from the I/O board. 2. Remove the coin-cell battery cable from the routing guide on the fan. 3. Using a plastic scribe, peel the coin-cell battery off the slot on the palm-rest and keyboard assembly. Installing the coin-cell battery Prerequisites If you are replacing a component, remove the existing component before performing the installation procedure.
Steps 1. Adhere the coin-cell battery to the slot on the palm-rest and keyboard assembly. 2. Lift the speaker cable and route the coin-cell battery cable through the routing guide on the fan. 3. Connect the coin-cell battery cable to the I/O board. Next steps 1.
Steps 1. Lift the flap to access the memory module. 2. Use your fingertips to carefully spread apart the securing-clips on each end of the memory-module slot until the memory module pops 3. Slide and remove the memory module from the memory-module slot. NOTE: Repeat step 2 to step 3 to remove any other memory modules installed in your computer.
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Steps 1. Lift the flap to access the memory-module slot. 2. Align the notch on the memory module with the tab on the memory-module slot. 3. Slide the memory module firmly at an angle, into the memory-module slot. 4. Press the memory module down until it clicks into place. NOTE: If you do not hear the click, remove the memory module and reinstall it.
Speakers Removing the speakers Prerequisites 1. Follow the procedure in Before working inside your computer. 2. Remove the base cover. About this task The following image indicates the location of the speakers and provides a visual representation of the removal procedure. Steps 1.
Steps 1. Using the alignment posts and rubber grommets, place the speakers on the slots of the palm-rest and keyboard assembly. 2. Route the speaker cable through the routing guides on the palm-rest and keyboard assembly. 3. Connect the speaker cable to the system board. Next steps 1.
Steps 1. In reverse sequential order (as indicated on the heat sink), loosen the seven captive screws that secure the heat sink to the system board. 2. Lift the heat sink off the system board. Installing the heat sink Prerequisites If you are replacing a component, remove the existing component before performing the installation procedure.
Steps 1. Align the screw holes on the heat sink with the screw holes on the system board. 2. In sequential order (as indicated on the heat sink), tighten the seven captive screws that secure the heat sink to the system board. Next steps 1.
Steps 1. Remove the three screws (M2.5x5) that secure the right display-hinge to the palm-rest and keyboard assembly. 2. Open the right display-hinge at an angle of 90 degrees. 3. Peel the tape that secures the power-adapter port cable to the system board. 4.
Steps 1. Place the power-adapter port into the slot on the palm-rest and keyboard assembly. 2. Replace the screw (M2x3) that secures the power-adapter port to the palm-rest and keyboard assembly. 3. Route the power-adapter port cable through the routing guide on the palm-rest and keyboard assembly. 4.
Steps 1. Remove the three screws (M2x2) that secure the touchpad bracket to the palm-rest and keyboard assembly. 2. Open the latch, and disconnect the touchpad cable from the touchpad. 3. Peel the tape that secures the touchpad to the palm-rest and keyboard assembly. 4.
Steps 1. Slide the touchpad into the slot on the palm-rest and keyboard assembly. 2. Replace the two screws (M2x2) that secure the touchpad to the palm-rest and keyboard assembly. 3. Adhere the tape that secures the touchpad to the palm-rest and keyboard assembly. 4.
Steps 1. Remove the screw (M2x3) that secures the solid-state drive thermal bracket to the palm-rest and keyboard assembly. 2. Lift the solid-state drive thermal bracket off the palm-rest and keyboard assembly. 3. Remove the screw (M2x3) that secures the solid-state drive to the solid-state drive bracket. 4.
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The following image indicates the location of the M.2 2230 solid-state drive and provides a visual representation of the installation procedure. Removing and installing components...
Steps 1. Remove the screw (M1.6x2.5) that secures the solid-state drive bracket to the palm-rest and keyboard assembly. 2. Turn the solid-state drive bracket at an angle of 180 degrees. 3. Insert the solid-state drive bracket into the other solid-state drive bracket slot on the palm-rest and keyboard assembly. 4.
Steps 1. Remove the screw (M2x3) that secures the solid-state drive thermal bracket to the palm-rest and keyboard assembly. 2. Lift the solid-state drive thermal bracket off the palm-rest and keyboard assembly. 3. Remove the screw (M2x3) that secures the solid-state drive to the solid-state drive bracket. 4.
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The following image indicates the location of the M.2 2280 solid-state drive and provides a visual representation of the installation procedure. NOTE: Perform step 1 to step 3 if you are replacing the M.2 2230 solid-state drive with an M.2 2280 solid-state drive. Removing and installing components...
Steps 1. Remove the screw (M1.6x2.5) that secures the solid-state drive bracket to the palm-rest and keyboard assembly. 2. Turn the solid-state drive bracket at an angle of 180 degrees. 3. Insert the solid-state drive bracket into the other solid-state drive bracket slot on the palm-rest and keyboard assembly. 4.
3. Lift the fan off the palm-rest and keyboard assembly. Installing the fan Prerequisites If you are replacing a component, remove the existing component before performing the installation procedure. About this task The following image indicates the location of the fan and provides a visual representation of the installation procedure. Steps 1.
About this task The following image indicates the location of the I/O-board and provides a visual representation of the removal procedure. Steps 1. Remove the two screws (M2.5x5) that secure the left display hinge to the palm-rest and keyboard assembly. 2.
Steps 1. Slide the I/O board into the slots on the palm-rest and keyboard assembly. 2. Align the screw hole on the I/O board with the screw hole on the palm-rest and keyboard assembly. 3. Replace the screw (M2x3) that secures the I/O board to the palm-rest and keyboard assembly. 4.
About this task The following image indicates the location of the power button with fingerprint reader and provides a visual representation of the removal procedure. Steps 1. Remove the two screws (M2x3) that secure the power-button bracket to the palm-rest and keyboard assembly. 2.
Steps 1. Align and place the power button, along with its cable, on the slot of the palm-rest and keyboard assembly. 2. Slide the power-button cable into the connector on the fingerprint reader-board and close the latch to secure the cable. 3.
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Steps 1. Peel the tape that secures the display cable to the system board. 2. Open the latch, and disconnect the display cable from the system board. 3. Remove the two screws (M2.5x5) that secure the left-display hinges to the palm-rest and keyboard assembly. 4.
5. Lift at an angle and slide the display assembly off the palm-rest and keyboard assembly. Installing the display assembly Prerequisites If you are replacing a component, remove the existing component before performing the installation procedure. About this task The following image indicates the location of the display assembly and provides a visual representation of the installation procedure. Removing and installing components...
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Steps 1. Slide the display assembly at an angle, and place the display assembly on the palm-rest and keyboard assembly. 2. Replace the two screws (M2.5x5) that secure the left-display hinge to the palm-rest and keyboard assembly. 3. Replace the three screws (M2.5x5) that secure the right-display hinge to the palm-rest and keyboard assembly. 4.
System board Removing the system board Prerequisites 1. Follow the procedure in Before working inside your computer. 2. Remove the base cover. 3. Remove the battery. 4. Remove the coin-cell battery. 5. Remove the memory modules. 6. Remove the M.2 2230 solid-state drive M.2 2280 solid-state drive, as applicable.
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Steps 1. Remove the three screws (M2.5x5) that secure the right-display hinge to the palm-rest and keyboard assembly.. 2. Open the hinge at an angle of 90 degrees. 3. Peel the tape that secures the USB Type-C port bracket to the system board. 4.
5. Peel the tape that secures the I/O-board cable to the system board. 6. Open the latch, and disconnect the I/O-board cable from the system board. 7. Disconnect the speaker cable from the system board. 8. Open the latch, and disconnect the touchpad cable from the system board. 9.
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Steps 1. Align and place the system board on the palm-rest and keyboard assembly. 2. Replace the two screws (M2x2) that secure the system board to the palm-rest and keyboard assembly. 3. Connect the display cable to the connector on the system board and close the latch to secure the cable. 4.
5. Connect the power-adapter port cable to the connector on the system board. 6. Align the screw holes on the USB Type-C port bracket with the screw holes on the system board. 7. Adhere the tape that secures the USB Type-C port bracket to the system board. 8.
Steps After performing the steps in the pre-requisites, you are left with the palm-rest and keyboard assembly. Installing the palm-rest and keyboard assembly Prerequisites If you are replacing a component, remove the existing component before performing the installation procedure. About this task The following image indicates the location of the palm-rest and keyboard assembly and provides a visual representation of the installation procedure.
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Steps Place the palm-rest and keyboard assembly on a clean and flat surface. Next steps 1. Install the system board. 2. Install the display assembly. 3. Install the power-button board. 4. Install the touchpad. 5. Install the power-adapter port. 6. Install the fan. 7.
Drivers and downloads When troubleshooting, downloading or installing drivers it is recommended that you read the Dell Knowledge Based article, Drivers and Downloads FAQ SLN128938. Drivers and downloads...
Boot Sequence allows you to bypass the System Setup–defined boot device order and boot directly to a specific device (for example: optical drive or hard drive). During the Power-on Self Test (POST), when the Dell logo appears, you can: •...
• STXXXX Drive (if available) NOTE: XXX denotes the SATA drive number. • Optical Drive (if available) • SATA Hard Drive (if available) • Diagnostics The boot sequence screen also displays the option to access the System Setup screen. One time boot menu To enter one time boot menu, turn on your computer, and then press F2 immediately.
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Table 4. System setup options—Advanced menu Advanced PowerNow! Enable Enables or disables the dynamic frequency scaling and power- saving technology for the AMD processor. Default: Enabled Virtualization Enables or disables the Virtualization technology. Default: Enabled Integrated NIC Enables or disables the on-board LAN controller. Default: Enabled USB Emulation Enables or disables the USB emulation feature.
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Default: Disabled SupportAssist System Resolution Auto OS Recovery Threshold Controls the automatic boot flow for SupportAssist System Resolution Console and for the Dell OS Recovery tool. Default: 2 SupportAssist OS Recovery Enables or disables the boot flow for the SupportAssist OS Recovery tool in the even of certain system errors.
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Enables or disables BIOS updates through UEFI capsule update packages. Default: Enabled WINDOWS SMM SECURITY MITIGATIONS TABLE (WSMT) Enables or disables configuration of platform features on Dell Client Systems with WSMT-enabled BIOS. Default: Enabled Table 6. System setup options—Boot menu...
Clearing BIOS (System Setup) and System passwords About this task To clear the system or BIOS passwords, contact Dell technical support as described at www.dell.com/contactdell. NOTE: For information on how to reset Windows or application passwords, refer to the documentation accompanying Windows or your application.
Check Steps 1. Turn on your computer. 2. As the computer boots, press the F12 key as the Dell logo appears. 3. On the boot menu screen, select the Diagnostics option. 4. Click the arrow at the bottom left corner.
You can also download it from the Dell Support website to troubleshoot and fix your computer when it fails to boot into their primary operating system due to software or hardware failures.
Backup media and recovery options It is recommended to create a recovery drive to troubleshoot and fix problems that may occur with Windows. Dell proposes multiple options for recovering Windows operating system on your Dell PC. For more information. see Dell Windows Backup Media and Recovery Options.
2. Turn off the modem. 3. Turn off the wireless router. 4. Wait for 30 seconds. 5. Turn on the wireless router. 6. Turn on the modem. 7. Turn on your computer. Flea power release About this task Flea power is the residual static electricity that remains on the computer even after it has been powered off and the battery has been disconnected from the system board.
Getting help and contacting Dell Self-help resources You can get information and help on Dell products and services using these self-help resources: Table 10. Self-help resources Self-help resources Resource location Information about Dell products and services www.dell.com My Dell Tips Contact Support In Windows search, type Contact Support, and press Enter.