Introduction
Welcome to the user manual for your new Casio Baby-G MSG-B100DG-9AJF watch. This timepiece is part of the G-MS series, designed for the modern, active individual, combining sophisticated style with robust functionality. Key features include Bluetooth connectivity for smartphone link functions, Tough Solar power for stable operation, and 10 ATM water resistance for daily use and water activities.
This manual provides detailed instructions on how to set up, operate, and maintain your watch to ensure optimal performance and longevity. Please read it thoroughly before using your watch.
Setup Guide
1. Initial Charging
Your MSG-B100DG-9AJF watch is equipped with Tough Solar technology, which converts light into electrical power. Before initial use, expose the watch face to bright light for several hours to ensure it is sufficiently charged. A low battery indicator may appear if the charge is insufficient.
- Optimal Charging: Place the watch where its face is exposed to direct sunlight or strong fluorescent light.
- Avoid Overheating: Do not place the watch in extremely hot locations (e.g., on a car dashboard under direct sun) while charging, as this can damage the watch.
2. Smartphone Link Setup (Bluetooth)
The watch can connect to your smartphone via Bluetooth for automatic time adjustment, world time settings, and other functions using the dedicated Casio CASIO WATCHES app.
- Download the App: Search for "CASIO WATCHES" (formerly G-SHOCK Connected) in your smartphone's app store (App Store for iOS, Google Play for Android) and install it.
- Enable Bluetooth: Ensure Bluetooth is enabled on your smartphone.
- Pairing Process:
- On the watch, hold down the ADJUST button (top left) for approximately two seconds until "CONNECT" flashes on the digital display.
- Open the CASIO WATCHES app on your smartphone and follow the on-screen instructions to pair the watch.
- Once pairing is successful, the watch will automatically adjust its time based on your smartphone's time.
For detailed pairing instructions and troubleshooting, refer to the app's help section or the official Casio website.
Operating Your Watch
Button Functions
| Button | Function (Short Press) | Function (Hold) |
|---|---|---|
| ADJUST (Top Left) | Used to enter and exit setting modes. | Initiates Bluetooth connection/pairing. |
| MODE (Bottom Left) | Cycles through watch modes (Timekeeping, World Time, Alarm, Stopwatch, Timer). | Not applicable for hold function in general mode cycling. |
| LIGHT (Top Right) | Illuminates the watch face. | Not applicable for hold function. |
| SEARCH (Bottom Right) | Used to adjust settings within modes, or initiate phone finder function. | Initiates phone finder (when connected via Bluetooth). |
Mode Navigation
Press the MODE button (bottom left) to cycle through the different watch modes:
- Timekeeping Mode: Displays current time, date, and day of the week. This is the default mode.
- World Time Mode: Displays the current time in a pre-selected city (World Time City).
- Alarm Mode: Allows setting and activating daily alarms.
- Stopwatch Mode: Measures elapsed time.
- Timer Mode: Counts down from a specified time.
Using Specific Functions
World Time
In World Time Mode, use the SEARCH button (bottom right) to cycle through pre-set world cities. To change the World Time City, use the CASIO WATCHES app for easier selection, or refer to the full manual for manual adjustment.
Alarm Setting
- Enter Alarm Mode by pressing the MODE button.
- Hold the ADJUST button until the alarm time starts flashing.
- Use the SEARCH and LIGHT buttons to adjust the hour and minute.
- Press ADJUST to save and exit.
Stopwatch
In Stopwatch Mode:
- Press SEARCH to start/stop the stopwatch.
- Press LIGHT to reset the stopwatch to zero.
Illumination (LED Light)
Press the LIGHT button (top right) to illuminate the watch face for easy viewing in low light conditions.
Phone Finder
If your watch is connected to your smartphone via Bluetooth, hold the SEARCH button (bottom right) in Timekeeping Mode. This will trigger an audible alert on your smartphone, helping you locate it.
Care and Maintenance
Cleaning Your Watch
Regular cleaning helps maintain the appearance and longevity of your watch.
- Case and Band: Wipe with a soft, dry cloth. For metal bands, a soft brush and mild soapy water can be used, followed by thorough rinsing and drying.
- Resin Band: Wash with water and dry thoroughly. Avoid solvents or harsh chemicals.
- Water Resistance: After exposure to saltwater, rinse the watch thoroughly with fresh water and dry it completely.
Water Resistance (10 ATM)
Your watch is rated for 10 ATM (100 meters) water resistance. This means it is suitable for daily use, showering, swimming, and snorkeling. However, it is not suitable for scuba diving or high-impact water sports.
- Important: Do not operate any buttons while the watch is wet or submerged in water.
- Ensure the crown (if applicable, though this model is button-operated) is fully pushed in before exposing to water.

Image: A rose gold Casio Baby-G watch partially submerged in water, illustrating its 10 ATM water resistance. This model is designed to withstand splashes, rain, and swimming.
Tough Solar Power Management
To ensure stable operation, regularly expose the watch face to light. Avoid prolonged storage in dark places, which can deplete the battery and cause functions to stop or become unstable.
- Power Saving: The watch may enter a power-saving mode when left in the dark for an extended period, turning off the display to conserve power.
- Battery Level Indicator: Monitor the battery level indicator (if available on the digital display) to ensure sufficient charge.
Troubleshooting
Time is Incorrect
- Check Bluetooth Connection: Ensure the watch is successfully paired with your smartphone and the CASIO WATCHES app is running. Perform a manual time adjustment via the app.
- Solar Charge Level: Insufficient charge can affect timekeeping accuracy. Expose the watch to bright light for charging.
- Home City Setting: Verify that your Home City setting is correct.
Cannot Connect to Smartphone
- Bluetooth On: Ensure Bluetooth is enabled on your smartphone.
- App Running: Make sure the CASIO WATCHES app is open and active.
- Watch in Pairing Mode: Hold the ADJUST button on the watch until "CONNECT" flashes.
- Distance: Keep the watch and smartphone within close proximity (typically 2 meters).
- Interference: Avoid areas with strong radio interference.
- Re-pair: If issues persist, try deleting the watch from your smartphone's Bluetooth device list and re-pairing from scratch.
Watch Display is Blank or Functions are Not Working
- Low Battery: The watch may be in power-saving mode or have a very low charge. Expose it to bright light for several hours.
- Reset: In rare cases, a full reset might be necessary. Refer to the full Casio manual for specific reset procedures, as this may clear all settings.

Image: A black Casio Baby-G watch with its digital display illuminated, showcasing the backlight feature for visibility in dark conditions.
Specifications
| Feature | Detail |
|---|---|
| Model Number | MSG-B100DG-9AJF |
| Brand | Casio (Baby-G G-MS Series) |
| Power Source | Tough Solar (Solar Powered) |
| Battery Type | 1 Lithium Metal battery (included) |
| Water Resistance | 10 ATM (100 meters) |
| Connectivity | Bluetooth® Smart (Smartphone Link) |
| Timekeeping | Analog and Digital Display |
| Functions | World Time, Stopwatch, Countdown Timer, Daily Alarm, Full Auto-calendar, LED Light (Super Illuminator), Battery Level Indicator, Hand Shift Feature, Phone Finder. |
| Case/Bezel Material | Stainless Steel / Resin |
| Band Material | Stainless Steel |
| Approx. Package Dimensions | 4.41 x 3.9 x 2.99 inches |
| Approx. Package Weight | 6.35 ounces |
| Date First Available | June 1, 2021 |

Image: The Casio Baby-G MSG-B100DG-9AJF watch in gold, highlighting its G-MS design, Bluetooth indicator, and digital display.

Image: A comparison of three Casio Baby-G MSG-B100 series watches in different finishes: black, rose gold, and gold. This illustrates the design consistency across color options.

Image: A rose gold Casio Baby-G watch on a wrist, positioned next to a tube of lipstick to provide a sense of scale and highlight its elegant design suitable for daily wear.
Warranty and Support
Your Casio Baby-G MSG-B100DG-9AJF watch comes with a manufacturer's warranty. The terms and duration of the warranty may vary by region and retailer. Please retain your proof of purchase for warranty claims.
For detailed warranty information, product support, frequently asked questions, and to download the full instruction manual, please visit the official Casio website or contact Casio customer service directly.
Official Casio Website: www.casio.com
Customer Support: Refer to the contact information provided on the Casio website for your specific region.





