1. What This Setting Does

Bluetooth connection is the wireless bridge between the JK BMS App and the hardware inside your battery. It allows you to:

• “Wake up” the battery so it starts working
• Monitor every individual cell voltage in your 48V pack
• Input critical safety settings for LiFePO4 chemistry

2. Why It Matters

A brand new JK BMS typically arrives with MOSFETs turned OFF. Without Bluetooth, you cannot turn the battery “ON.” The app also acts as your primary diagnostic tool when the BMS shuts down.

3. Before You Change Anything

• Activation Step: Apply brief charge voltage OR press the physical power button.
• Permissions: On Android, enable Location Services (GPS).
• Passwords: Connection = 1234, Settings = 123456

4. Step-by-Step Setup

1. Download the official “JK BMS” app from App Store/Play Store
2. Toggle Bluetooth OFF → ON to refresh
3. Open the JK App (do not pair in system settings)
4. Tap Scan/Search in the app
5. Select your BMS (e.g., JK-B2A… or JK-PB…)
6. Enter password 1234

5. Recommended Values

You can rename your device later (e.g., “Main Solar” or “48V House Bank”). Keep the default connection password 1234 until your system is stable.

6. Real-World Example

A DIY builder connects 16 cells but sees nothing in the app. They briefly touch a 48V charger to the terminals, the BMS beeps, they hit “Scan,” enter 1234, and instantly see all 16 cell voltages on their phone.

7. Common Mistakes

• Pairing in system Bluetooth settings instead of inside the app
• Denying Location permissions on Android
• Trying multiple devices at once (only one phone can connect)

8. Troubleshooting

• Device Not Found: Ensure BMS is awake (look for LED blink or beep)
• Password Errors: Try 123456 or 000000
• Connection Loops: Move closer (range is ~15–20 ft)

9. Safety Notes ⚠️

• Never connect or change settings while actively wiring the battery
• If constant beep occurs, check app status immediately for alarms

10. Quick Summary

1. Activate the BMS with charger or button
2. Enable Bluetooth + Location
3. Scan only through the JK App
4. Use 1234 to connect