Q1. My phone's battery percentage is inaccurate and it often shuts down with 20% charge left. Can this be fixed?

This is a very common software issue reported for this model. Flashing the stock firmware resets the battery calibration files. After flashing, it is highly recommended to perform a full charge cycle (drain the battery completely until it shuts off, then charge it to 100% uninterrupted) to help the system relearn the battery levels accurately.

Q2. The fingerprint scanner on my Magic C has become slow and fails to recognize my finger. Will this help?

Yes, it often can. Over time, the software and calibration data for the sensor can become corrupted. A clean firmware installation restores the original drivers and calibration data. For the best results, be sure to delete your old fingerprints and re-register them after you have flashed the firmware.

Q3. The sound from my earpiece is very quiet or crackles during phone calls. What's the cause?

While this could be a hardware issue with the speaker, it is frequently a software bug related to the phone's audio codecs. Flashing the stock ROM is an excellent troubleshooting step as it resets all system audio settings and drivers to their factory defaults, which can often fix the problem.

BQ Mobile BQ-5730L Magic C Firmware (Stock ROM)

The BQ Mobile BQ-5730L Magic C is a budget-friendly smartphone from 2018 that features a modern 18:9 aspect ratio display and runs on Android 9 Pie. While it offers a decent set of features for its class, including a fingerprint scanner and Face Unlock, users have reported several specific software-related issues over its lifespan. The most common complaints include an inaccurate battery indicator that causes sudden shutdowns, an unreliable fingerprint scanner, and poor audio quality from the earpiece. Flashing the official stock firmware is the most reliable way to fix these bugs by reinstalling a clean and stable version of the operating system.

ℹ️ Important Note:
This phone is powered by a UNISOC (Spreadtrum) chipset and requires the SPD Upgrade Tool to install the firmware. This procedure will completely erase all your personal data. Ensure you have backed up your important files before you begin.

⚠️ Prerequisites: Before You Begin

Click Here for the Essential Pre-Flashing Checklist

Backup Your Data: All your contacts, photos, and files on the phone’s internal storage will be permanently wiped.
Charge The Battery: To prevent the phone from shutting down during the update, ensure the battery is charged to at least 50%.
Windows PC & USB Cable: You will need a Windows computer and a standard micro USB cable to perform the flash.

📱 Quick Device Specifications

Device: BQ Mobile BQ-5730L Magic C
Chipset: UNISOC SC9863A
Display: 5.7″ HD+ IPS (1440×720)
Operating System: Android 9 Pie
RAM: 2GB
Storage: 16GB
Battery: 2700 mAh

🛠 Required Tools & Downloads

File / Tool	Download Link
SPD Upgrade Tool	Download Tool
UNISOC/SPD SCI USB Drivers	Download Drivers

⬇️ BQ Mobile BQ-5730L Magic C Stock ROM / Firmware

Android Version	Build Number	Chipset	Download Link
9 Pie	V01_180610	UNISOC SC9863A	Download (Google Drive)

Quick Steps to Flash BQ-5730L Magic C Firmware

Download and install the SPD SCI USB Drivers on your Windows PC.
Extract the firmware ZIP file (BQ_Mobile_BQ-5730L_..._MIRA.zip) to get the .pac file inside.
Extract and run the SPD Upgrade Tool (UpgradeDownload.exe).
Click the single gear icon (“Load Packet”) and select the firmware .pac file.
Click the play icon (“Start Downloading”). Power off your phone completely.
Press and hold the Volume Down key, and while holding it, connect the phone to the PC. The tool will detect the phone and start flashing. You can release the key once the progress bar appears.
A green “Passed” message will appear upon completion. Disconnect your phone and power it on.

For a more detailed, step-by-step guide on this process, please refer to our main tutorial:
👉 Full Tutorial: How to Flash Firmware with the SPD Upgrade Tool

❓ Frequently Asked Questions (FAQs)

Q1. My phone’s battery percentage is inaccurate and it often shuts down with 20% charge left. Can this be fixed?: This is a very common software issue reported for this model. Flashing the stock firmware resets the battery calibration files. After flashing, it is highly recommended to perform a full charge cycle (drain the battery completely until it shuts off, then charge it to 100% uninterrupted) to help the system relearn the battery levels accurately.
Q2. The fingerprint scanner on my Magic C has become slow and fails to recognize my finger. Will this help?: Yes, it often can. Over time, the software and calibration data for the sensor can become corrupted. A clean firmware installation restores the original drivers and calibration data. For the best results, be sure to delete your old fingerprints and re-register them after you have flashed the firmware.
Q3. The sound from my earpiece is very quiet or crackles during phone calls. What’s the cause?: While this could be a hardware issue with the speaker, it is frequently a software bug related to the phone’s audio codecs. Flashing the stock ROM is an excellent troubleshooting step as it resets all system audio settings and drivers to their factory defaults, which can often fix the problem.

🔧 Device Troubleshooting

The phone is stuck in a bootloop after a successful flash: This can happen if old data conflicts with the new system. Boot into recovery mode (usually Power + Volume Down), and perform a “Wipe data/factory reset.” This will allow the phone to boot correctly.
SPD Upgrade Tool gets stuck on “Checking BAUD”: This is the most common flashing error and points to a driver or connection problem. Ensure you have installed the correct SPD SCI drivers. Try a different USB port and a known-good USB cable. Critically, make sure the phone is fully powered off before you press and hold the Volume Down button and connect it to the PC.
I forgot my Google account and am stuck after a reset (FRP Lock): Flashing this firmware will completely wipe the phone, which includes removing the Factory Reset Protection (FRP) lock. After the flash, you will be able to set up the device with a new Google account.