Oppo A3s Cph1803 Flash File -
How to Flash Oppo A3s (CPH1803): Firmware Download & Step-by-Step Guide
- CPH1803EX_11_A.15_181109 (Android 8.1 Oreo – Most stable)
- CPH1803EX_11_A.21 (Latest security patch for this model)
- Boot: Contains the kernel. Flashing this fixes bootlogo hangs
MSM Download Tool: The official Oppo tool (often requires authorized login). oppo a3s cph1803 flash file
4. Required Tools & Drivers
| Tool | Purpose | Download Notes |
| :--- | :--- | :--- |
| Qualcomm USB Driver | PC to recognize device in EDL mode | Official from Qualcomm |
| Oppo USB Driver | ADB/Fastboot mode | Oppo support site |
| QFIL (v2.0.2.x) | Flashing rawprogram XML files | Included in Qualcomm HS-USB QDLoader 9008 driver package |
| Miko / UnlockTool (Paid) | Alternative for auth bypass | Commercial tool |
| Python + edl tool (Free) | Open-source EDL client | GitHub bkerler/edl | How to Flash Oppo A3s (CPH1803): Firmware Download
Use a high-quality or original USB cable for a stable connection. PC/Laptop: A Windows computer is required to run the flashing tools. Required Tools and Files To flash the , you typically need the following: Official Flash File: CPH1803EX_11_A
- A Windows PC (Windows 7, 8, or 10): Linux and Mac are not supported by most flashing tools.
- SP Flash Tool v5.1824 or Higher: The official flashing utility for MediaTek chipsets.
- MTK USB Drivers (VCOM Drivers): Allows your PC to communicate with the phone in pre-loader mode.
- OPPO USB Drivers: For normal ADB/fastboot commands (optional but helpful).
- Micro USB Cable: A high-quality data cable (not just a charging cable). Poor cables cause "DRAM failed" errors.
- Backup: Flashing will wipe everything – photos, contacts, and apps. Proceed only if you have backed up to Google Drive or an SD card.
- Battery Charge: Ensure your OPPO A3S is at least 60% charged.
Once the tool detects the device (usually shown as "Qualcomm HS-USB QDLoader 9008"), click the Start button in the tool.
Step-by-step (concise, general procedure)
- Confirm exact model (Settings → About phone or label under battery).
- Backup all data.
- Download matching CPH1803 ROM package and verify checksum if provided.
- Install USB drivers (ADB + Qualcomm QDLoader).
- Extract ROM package on PC; read included Readme.
- Use the specified flash tool (RFT/MSM) per package instructions.
- Put phone in required connection mode (power off + hold volume keys or EDL).
- Start flashing; do NOT disconnect or power off PC/device.
- When finished, reboot and perform factory reset/wipe cache if recommended.