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Dell Latitude 7490 CMOS Battery Replacement

Introduction

Use this guide to replace the CMOS battery in your Dell Latitude 7490 laptop.

If your laptop shows a BIOS configuration screen every time it's powered on, the CMOS battery may have died. Replace the CMOS battery to retain certain boot settings on your laptop.

What you need

  1. Dell Latitude 7490 CMOS Battery Replacement, Prepare your laptop for disassembly: step 1, image 1 of 2 Dell Latitude 7490 CMOS Battery Replacement, Prepare your laptop for disassembly: step 1, image 2 of 2

    • Allow your laptop's battery to drain below 25% before starting this repair—a charged battery may catch fire if damaged.

    • Unplug all cables and fully shut down your laptop.

    Edit

  2. Dell Latitude 7490 CMOS Battery Replacement, Flip your laptop over: step 2, image 1 of 1

    • Flip your laptop over so the rubber feet strips are facing up.

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  3. Dell Latitude 7490 CMOS Battery Replacement, Loosen the captive screws: step 3, image 1 of 2 Dell Latitude 7490 CMOS Battery Replacement, Loosen the captive screws: step 3, image 2 of 2

    • Use a Phillips screwdriver to fully loosen the eight captive screws securing the back cover.

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  4. Dell Latitude 7490 CMOS Battery Replacement, Insert an opening pick: step 4, image 1 of 3 Dell Latitude 7490 CMOS Battery Replacement, Insert an opening pick: step 4, image 2 of 3 Dell Latitude 7490 CMOS Battery Replacement, Insert an opening pick: step 4, image 3 of 3

    • Plastic clips secure the back cover to the frame. You'll hear and feel them release as you work.

    • Insert the long side of an opening pick between the top right corner of the back cover and frame.

    • Pry the back cover up to release the clips securing the top right corner.

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  6. Dell Latitude 7490 CMOS Battery Replacement, Release the clips: step 5, image 1 of 3 Dell Latitude 7490 CMOS Battery Replacement, Release the clips: step 5, image 2 of 3 Dell Latitude 7490 CMOS Battery Replacement, Release the clips: step 5, image 3 of 3

    • Slide the opening pick down the right edge and around the bottom right corner to release the clips.

    Edit

  7. Dell Latitude 7490 CMOS Battery Replacement: step 6, image 1 of 3 Dell Latitude 7490 CMOS Battery Replacement: step 6, image 2 of 3 Dell Latitude 7490 CMOS Battery Replacement: step 6, image 3 of 3

    • Slide the opening pick along the front edge and up to the top left corner to release the remaining clips securing the back cover.

    Edit

  8. Dell Latitude 7490 CMOS Battery Replacement, Remove the back cover: step 7, image 1 of 3 Dell Latitude 7490 CMOS Battery Replacement, Remove the back cover: step 7, image 2 of 3 Dell Latitude 7490 CMOS Battery Replacement, Remove the back cover: step 7, image 3 of 3

    • Remove the back cover.

    • During reassembly, lay the back cover on the frame and press down firmly around the perimeter to engage all the clips.

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  9. Dell Latitude 7490 CMOS Battery Replacement, Disconnect the battery: step 8, image 1 of 2 Dell Latitude 7490 CMOS Battery Replacement, Disconnect the battery: step 8, image 2 of 2

    • Grip the plastic tab on the battery connector and pull straight up to disconnect it.

    • During reassembly, align this connector over its socket and press down until it clicks into place. If it doesn't connect, re‑align it and try again.

    Edit

  10. Dell Latitude 7490 CMOS Battery Replacement, Disconnect the CMOS battery: step 9, image 1 of 3 Dell Latitude 7490 CMOS Battery Replacement, Disconnect the CMOS battery: step 9, image 2 of 3 Dell Latitude 7490 CMOS Battery Replacement, Disconnect the CMOS battery: step 9, image 3 of 3

    • Use clean fingernails to pull the CMOS battery connector out of its socket on the motherboard's bottom left corner.

    • If your fingernails aren't long enough, use a spudger to push on alternating sides of the connector to "walk" it out of its socket.

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  11. Dell Latitude 7490 CMOS Battery Replacement, Pry up the CMOS battery: step 10, image 1 of 2 Dell Latitude 7490 CMOS Battery Replacement, Pry up the CMOS battery: step 10, image 2 of 2

    • Adhesive secures the CMOS battery to the frame.

    • Insert an opening pick between the left edge of the CMOS battery and the frame.

    • Use your pick to pry up the CMOS battery and separate the adhesive securing it.

    • If you're having trouble, heat an iOpener and apply it to the battery for two minutes. Alternatively, you can use a hair dryer to heat the battery.

    Edit

  12. Dell Latitude 7490 CMOS Battery Replacement, Remove the CMOS battery: step 11, image 1 of 3 Dell Latitude 7490 CMOS Battery Replacement, Remove the CMOS battery: step 11, image 2 of 3 Dell Latitude 7490 CMOS Battery Replacement, Remove the CMOS battery: step 11, image 3 of 3
    Tool used on this step:
    Tesa 61395 Tape
    $5.99
    Buy

    • Remove the CMOS battery, using your fingers to guide its wires out from under the speaker wires.

    • During reassembly:

    • Reconnect the CMOS battery.

    • Apply double-sided tape such as Tesa Tape to the battery and press it into place on the frame.

    Edit
Conclusion

To reassemble your device, follow these instructions in reverse order.

Take your e-waste to an R2 or e-Stewards certified recycler.

Repair didn’t go as planned? Try some basic troubleshooting, or ask our Answers community for help.

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Spencer Day

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