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Casio fx-300ES Plus 2nd Edition Battery Replacement

Introduction

This guide shows you how to replace the LR44 battery in your Casio fx-300ES Plus 2nd edition calculator (model # FX-300ESPLS2).

The battery is what powers your calculator and is subject to drain over time. If you notice your display is too dim, and adjusting contrast does not appear to fix this, or figures do not appear immediately after your calculator turns on, the battery requires replacing.

Before you begin the repair, make sure your calculator is powered off.

What you need

  1. Casio fx-300ES Plus 2nd Edition Battery Replacement, Battery Replacement: step 1, image 1 of 1

    • Press (Shift + AC) to turn off the calculator.

    Edit

  2. Casio fx-300ES Plus 2nd Edition Battery Replacement: step 2, image 1 of 3 Casio fx-300ES Plus 2nd Edition Battery Replacement: step 2, image 2 of 3 Casio fx-300ES Plus 2nd Edition Battery Replacement: step 2, image 3 of 3

    • Use a Phillips #00 screwdriver to remove the six 7.5 mm screws from the back panel.

    • Insert an opening pick in the seam between the top and bottom casing.

    • Slide it around the perimeter of the calculator to release the clips that connect the front and back panels.

    • Carefully separate the front and back halves of the calculator casing.

    Edit

  3. Casio fx-300ES Plus 2nd Edition Battery Replacement: step 3, image 1 of 3 Casio fx-300ES Plus 2nd Edition Battery Replacement: step 3, image 2 of 3 Casio fx-300ES Plus 2nd Edition Battery Replacement: step 3, image 3 of 3

    • Use a plastic spudger or opening pick to remove the old battery.

    Edit

  5. Casio fx-300ES Plus 2nd Edition Battery Replacement: step 4, image 1 of 1

    • Insert the new LR44 battery into the compartment with the positive (+) side facing up.

    Edit

  6. Casio fx-300ES Plus 2nd Edition Battery Replacement: step 5, image 1 of 2 Casio fx-300ES Plus 2nd Edition Battery Replacement: step 5, image 2 of 2

    • Replace the panel on the back of the calculator and use a Phillips #00 screwdriver to secure the six 7.5 mm Philips #00 screws.

    Edit

  7. Casio fx-300ES Plus 2nd Edition Battery Replacement: step 6, image 1 of 2 Casio fx-300ES Plus 2nd Edition Battery Replacement: step 6, image 2 of 2

    • Power on the calculator, then bring up the 'clear' menu by pressing (SHIFT + 9).

    Edit

  8. Casio fx-300ES Plus 2nd Edition Battery Replacement: step 7, image 1 of 3 Casio fx-300ES Plus 2nd Edition Battery Replacement: step 7, image 2 of 3 Casio fx-300ES Plus 2nd Edition Battery Replacement: step 7, image 3 of 3

    • Perform a restoration of the calculator's default settings.

    • The order to press is (SHIFT, 9, 1, =).

    Edit
Conclusion

You've done it! ;)

One other person completed this guide.

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Andrei John Tabanao

Member since: 01/07/25

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York University, Team 3-3, Woodhouse Winter 2025 Member of York University, Team 3-3, Woodhouse Winter 2025

YORK-WOODHOUSE-W25S3G3

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