Contents Chapter 1: Working inside your computer..................5 Safety instructions................................5 Before working inside your computer........................5 After working inside your computer..........................8 Chapter 2: Removing and installing components................9 Recommended tools................................9 Major components of Inspiron 14 Plus 7420......................... 9 Screw list....................................11 Base cover...................................
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Updating the BIOS from the F12 One-Time boot menu..................61 Chapter 5: Troubleshooting......................63 Handling swollen Lithium-ion batteries........................63 Locate the Service Tag or Express Service Code of your Dell computer ..........63 System-diagnostic lights..............................64 SupportAssist | On-board Diagnostics.........................65 Recovering the operating system..........................65 WiFi power cycle................................
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.
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Ensure that your computer is shut down and the AC adapter is disconnected. a. Hold <B> key on the keyboard and press the power button for 3 seconds or until the Dell logo appears on the screen. b. Press any key to continue.
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It is recommended that all field service technicians use the traditional wired ESD grounding wrist strap and protective anti-static mat at all times when servicing Dell products. In addition, it is critical that technicians keep sensitive parts separate from all insulator parts while performing service and that they use anti-static bags for transporting sensitive components.
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. After working inside your computer About this task CAUTION: Leaving stray or loose screws inside your computer may severely damage your computer.
Removing and installing components NOTE: The images in this document may differ from your computer depending on the configuration you ordered. Recommended tools The procedures in this document may require the following tools: ● Phillips screwdriver #0 ● Phillips screwdriver #1 ●...
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1. Base cover 2. Right speaker 3. Right fan Removing and installing components...
21. I/O board 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 five screws (M2x4) that secure the base cover to the palm-rest and keyboard assembly. 2. Loosen the two captive screws that secure the base cover to the palm-rest and keyboard assembly. 3. Using a plastic scribe, pry the base cover from the bottom left and continue to work on the sides to open the base cover. 4.
Steps 1. Place and snap the base cover into place on the palm-rest and keyboard assembly. 2. Tighten the two captive screws that secure the base cover to the palm-rest and keyboard assembly. 3. Replace the five screws (M2x4) that secure the base cover to the palm-rest and keyboard assembly. Next steps 1.
● 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.
Installing the battery Prerequisites If you are replacing a component, remove the existing component before performing the installation process. About this task The following image(s) indicate the location of the battery and provides a visual representation of the installation procedure. Steps 1.
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If you are replacing the M.2 2280 solid-state drive (shipped with the computer) with an M.2 2230 solid-state drive, a mounting bracket for the M.2 2230 solid-state drive is required. Please contact Dell support to purchase the mounting bracket for the M.2 2230 solid-state drive.
If you are replacing the M.2 2280 solid-state drive (shipped with the computer) with an M.2 2230 solid-state drive, a mounting bracket for the M.2 2230 solid-state drive is required. Please contact Dell support to purchase the mounting bracket for the M.2 2230 solid-state drive.
Steps 1. Align the notch on the M.2 2230 solid-state drive with the screw (M2x2) on the M.2 2230 solid-state drive bracket. 2. Tighten the screw (M2x2) that secures the M.2 2230 solid-state drive to the M.2 2230 solid-state drive bracket. 3.
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If you are replacing the M.2 2280 solid-state drive (shipped with the computer) with an M.2 2230 solid-state drive, a mounting bracket for the M.2 2230 solid-state drive is required. Please contact Dell support to purchase the mounting bracket for the M.2 2230 solid-state drive.
If you are replacing the M.2 2280 solid-state drive (shipped with the computer) with an M.2 2230 solid-state drive, a mounting bracket for the M.2 2230 solid-state drive is required. Please contact Dell support to purchase the mounting bracket for the M.2 2230 solid-state drive.
Next steps 1. Install the base cover. 2. Follow the procedure in After working inside your computer. Memory module Removing the memory module Prerequisites 1. Follow the procedure in Before working inside your computer. NOTE: Ensure that your computer is in Service Mode. For more information see, step 6 in Before working inside your computer.
Steps 1. Lift the Mylar to access the memory module. 2. Using your fingertips, carefully spread apart the securing-clips on each end of the memory-module slot until the memory module pops-up. 3. Remove the memory module from the memory-module slot on the system board. Installing the memory module Prerequisites If you are replacing a component, remove the existing component before performing the installation process.
3. Slide the memory module into the memory-module slot on the system board. 4. Press down on the memory module till the securing clips click, locking the memory module in place. Next steps 1. Install the base cover. 2. Follow the procedure in After working inside your computer.
2. Lift the wireless-card bracket off the wireless card. 3. Disconnect the antenna cables from the wireless card. 4. Slide and remove the wireless card from the M.2 card slot on the system board. Installing the wireless card Prerequisites If you are replacing a component, remove the existing component before performing the installation process. About this task The following image(s) indicate the location of the wireless card and provides a visual representation of the installation procedure.
3. Slide the wireless card into the M.2 card slot on the system board. 4. Place the wireless-card bracket on the wireless card. 5. Replace the screw (M2x3) that secures the wireless card and wireless-card bracket to the system board. Next steps 1.
Steps 1. Peel off the tape that secures the display-cable connector latch to the system board. 2. Open the latch and disconnect the display cable from the system board. 3. Open the display assembly to a 90-degree angle and place the computer on the edge of a table. 4.
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Steps 1. Place the computer on the edge of a table. Removing and installing components...
2. Hold the display assembly against the edge of the table, aligning the screw holes on the display hinges with the screw holes on the palm-rest and keyboard assembly. 3. Replace the five screws (M2.5x5) that secure the display hinges to the palm-rest and keyboard assembly. 4.
5. Lift the power-adapter port, along with its cable, off the palm-rest and keyboard assembly. Installing the power-adapter port Prerequisites If you are replacing a component, remove the existing component before performing the installation process. About this task The following image(s) indicate the location of the power-adapter port and provides a visual representation of the installation procedure.
NOTE: Ensure that your computer is in Service Mode. For more information see, step 6 in Before working inside your computer. 2. Remove the base cover. 3. Remove the heat sink. About this task The following image(s) indicate the location of the I/O board and provides a visual representation of the removal procedure. Steps 1.
Steps 1. Place the I/O board on the palm-rest and keyboard assembly. 2. Align the screw holes on the I/O board with the screw holes on the palm-rest and keyboard assembly. 3. Replace the two screws (M2x3) that secure the I/O board to the palm-rest and keyboard assembly. 4.
Steps 1. Disconnect the left fan cable from the system board. 2. Remove the two screws (M2x3) that secure the left fan to the palm-rest and keyboard assembly. 3. Lift the left fan off the palm-rest and keyboard assembly. Installing the left fan Prerequisites If you are replacing a component, remove the existing component before performing the installation process.
Steps 1. Place the left fan on the palm-rest and keyboard assembly. 2. Align the screw holes on the left fan with the screw holes on the palm-rest and keyboard assembly. 3. Replace the two screws (M2x3) that secure the left fan to the palm-rest and keyboard assembly. 4.
Steps 1. Disconnect the right fan cable from the system board. 2. Remove the two screws (M2x3) that secure the right fan to the palm-rest and keyboard assembly. 3. Lift the right fan off the palm-rest and keyboard assembly. Installing the right fan Prerequisites If you are replacing a component, remove the existing component before performing the installation process.
Steps 1. Place the right fan on the palm-rest and keyboard assembly. 2. Align the screw holes on the right fan with the screw holes on the palm-rest and keyboard assembly. 3. Replace the two screws (M2x3) that secure the right fan to the palm-rest and keyboard assembly. 4.
Steps 1. Disconnect the left fan cable from the system board and lift the left fan cable off the heat sink. 2. In reverse sequential order (4>3>2>1) loosen the four captive screws that secure the heat sink to the system board. NOTE: The number of screws varies depending on the configuration ordered.
Steps 1. Place the heat sink on the system board. 2. Align the screw holes on the heat sink to the screw holes on the system board. 3. In sequential order (1>2>3>4) tighten the four captive screws that secure the heat sink to the system board. NOTE: The number of screws varies depending on the configuration ordered.
Steps 1. Open the latch and disconnect the power-button board cable from the system board. 2. Remove the screw (M2x3) that secures the power-button board to the palm-rest and keyboard assembly. 3. Lift the power-button board and its cable off the palm-rest and keyboard assembly. Installing the power-button board Prerequisites If you are replacing a component, remove the existing component before performing the installation process.
Steps 1. Align and place the power-button board on the palm-rest and keyboard assembly. 2. Replace the screw (M2x3) that secures the power-button board to the palm-rest and keyboard assembly. 3. Connect the power-button board cable to the system board and close the latch. Next steps 1.
Steps 1. Peel off the Mylar that covers the fingerprint-reader cable. 2. Peel off the tape that secures the fingerprint-reader cable to the palm-rest and keyboard assembly. 3. Open the latch and disconnect the fingerprint-reader cable from the I/O board. Steps 1 to 3 are applicable to computers shipped with a fingerprint reader.
Steps 1. Align the screw hole on the power button with optional fingerprint reader with the screw hole on the palm-rest and keyboard assembly. 2. Replace the screw (M2x3) that secures the power button with optional fingerprint reader to the palm-rest and keyboard assembly.
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6. Remove the wireless card. 7. Remove the right fan. 8. Remove the heat sink. About this task The following image indicates the connectors and M.2 card slots on your system board. 1. Power-adapter port cable 2. Display cable 3. Right fan cable 4.
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Steps 1. Open the latch and disconnect the power-button board cable from the system board. 2. Peel the tape that secures the power-adapter port cable to the system board. 3. Disconnect the power-adapter port cable from the system board. 4. Peel off the tape that secures the display-cable connector latch to the system board. 5.
8. Open the latch and disconnect the keyboard cable from the system board. 9. Open the latch and disconnect the keyboard-backlight cable from the system board. 10. Disconnect the speaker cable from the system board. 11. Open the latch and disconnect the touchpad cable from the system board. 12.
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Steps 1. Install the system board at an angle and ensure that the ports are properly aligned with the port openings. 2. Align the screw holes on the system board with the screw holes on the palm-rest and keyboard assembly. 3.
7. Connect the display cable to the system board and close the latch. 8. Adhere the tape that secures the display-cable connector latch to the system board. 9. Align the screw holes on Type-C port bracket with the screw holes on the system board. 10.
Steps 1. Peel off the tapes that secure the antenna cables to the palm-rest and keyboard assembly. 2. Lift the antenna cables and move them out of the way. 3. Peel off the tape that secures the speaker cable to the palm-rest and keyboard assembly. 4.
Steps 1. Using the alignment posts, place the left speaker and the right speaker on the palm-rest and keyboard assembly. 2. Route the speaker cable through the routing guides on the palm-rest and keyboard assembly. 3. Adhere the tape that secures the speaker cable to the palm-rest and keyboard assembly. 4.
10. Remove the power-button board. 11. Remove the power button with optional fingerprint reader. 12. Remove the system board. 13. Remove the speakers. About this task The following image(s) indicate the location of the palm-rest and keyboard assembly and provides a visual representation of the removal procedure.
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Steps Place the palm-rest and keyboard assembly on a flat and clean surface and perform the tasks in Next steps to install the palm-rest and keyboard assembly. NOTE: The palm-rest and keyboard assembly consists of the following: ● Palm-rest ● Keyboard ●...
Drivers and downloads When troubleshooting, downloading or installing drivers it is recommended that you read the Dell Knowledge Based article, Drivers and Downloads FAQ 000123347. Drivers and downloads...
System setup CAUTION: Unless you are an expert computer user, do not change the settings in the BIOS Setup program. Certain changes can make your computer work incorrectly. NOTE: Depending on the computer and its installed devices, the items listed in this section may or may not be displayed. NOTE: Before you change BIOS Setup program, it is recommended that you write down the BIOS Setup program screen information for future reference.
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: ● Access System Setup by pressing F2 key ●...
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Table 4. System setup options—System information menu (continued) Overview Processor ID Displays the processor identification code. Processor L2 Cache Displays the processor L2 Cache size. Processor L3 Cache Displays the processor L3 Cache size. Microcode Version Displays the microcode version. Intel Hyper-Threading Capable Displays whether the processor is Hyper-Threading (HT) capable.
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Table 5. System setup options—Boot Configuration menu (continued) Boot Configuration Expert Key Management Enable Custom Mode Allows the PK, KEK, db, and dbx security key databases to be modified. Default: OFF NOTE: If Custom Mode is not enabled, any changes made with respect to the keys will not be saved.
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Enables or disables cloud Service OS recovery if the main OS fails to boot within the number of failures equal or greater than the value specified by Dell Auto OS Recovery Threshold, and local Service does not boot, or is not installed.
Table 12. System setup options—Pre-boot Behavior menu Pre-boot Behavior Adapter warnings Enable Adapter warnings Enables or disables the computer to display adapter warning messages when adapters with too little power capacity are detected. Default: ON Warnings and Errors Selects an action on encountering a warning or error during boot. Default: Prompt on Warnings and Errors.
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.
One-Time boot menu on the computer. Most of the Dell computers built after 2012 have this capability, and you can confirm by booting your computer to the F12 One-Time Boot Menu to see if BIOS FLASH UPDATE is listed as a boot option for your computer. If the option is listed, then the BIOS supports this BIOS update option.
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● AC power adapter that is connected to the computer ● Functional computer battery to flash the BIOS Perform the following steps to perform the BIOS update flash process from the F12 menu: CAUTION: Do not turn off the computer during the BIOS update process. The computer may not boot if you turn off your computer.
● Using a non-Dell or incompatible battery may increase the risk of fire or explosion. Replace the battery only with a compatible battery purchased from Dell that is designed to work with your Dell computer. Do not use a battery from other computers with your computer.
The following diagnostic light codes and recommended solutions are intended for Dell service technicians to troubleshoot problems. You should only perform troubleshooting and repairs as authorized or directed by the Dell technical support team. Damage due to servicing that is not authorized by Dell is not covered by your warranty. Table 15. Diagnostic-light codes...
It enables you to diagnose hardware issues, repair your computer, back up your files, or restore your computer to its factory state. 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.
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Steps 1. Turn off your computer. 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. Troubleshooting...
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 16. Self-help resources Self-help resources Resource location Information about Dell products and services www.dell.com My Dell app...