The ZTE Maven 3 (model Z835) is a compact, entry-level 4G smartphone designed for the AT&T prepaid network in the USA. It focuses on core communication essentials, powered by a Qualcomm Snapdragon processor and featuring a 5.0-inch display. This guide provides the official stock ROM, a low-level QFIL / EDL package, designed to unbrick a hard-bricked phone, resolve persistent software errors, bypass a Google FRP lock, or restore the device to its original factory state.
Important: This is an advanced unbricking procedure. This firmware is specifically for the ZTE Maven 3 (Z835). The flashing process requires your phone to be in EDL Mode (9008), and the process will erase all data.
Quick Device Specs
- Device: ZTE Maven 3 (Z835)
- Release year: 2017
- Chipset: Qualcomm Snapdragon 210 (MSM8909)
- Display: 5.0″ TFT Display
- Battery: 2070 mAh
- Original OS: Android 7.1 (Nougat)
Required Downloads
To flash a Qualcomm device in EDL mode, you will need the specific QPST suite and drivers. You can find the downloads for these in our main guide linked below.
- QPST & QFIL Flash Tool
- Qualcomm QDLoader USB Drivers
Unbrick Firmware (QFIL)
| Region / Carrier | Build | Android | Type | Download | Chipset |
|---|---|---|---|---|---|
| USA (AT&T) | V1.0.0B13 | 7.1 | QFIL EDL Unbrick ROM | Download | Qualcomm |
How to Flash the Stock Firmware
Restoring a bricked ZTE Maven 3 requires a Windows PC and the QFIL tool. The process involves installing the correct Qualcomm drivers, forcing your phone into EDL Mode by holding Volume Up + Down and connecting the USB cable, loading the firehose programmer and XML files from the firmware, and then starting the download.
For a detailed, step-by-step guide with screenshots and tool download links, please follow our comprehensive pillar guide: How to Use QFIL to Flash Qualcomm Devices.
Device-Specific Troubleshooting for ZTE Maven 3 (Z835)
- “No Port Available” / Driver Issues: This is the most common problem. If QFIL doesn’t see the “Qualcomm HS-USB QDLoader 9008” port, your drivers are not installed correctly. You must disable Driver Signature Enforcement in Windows before running the driver installer. Reboot your PC after installation and try again.
- Entering EDL Mode: Ensure the phone is completely powered off. Press and hold both Volume Up and Volume Down buttons simultaneously. While holding them, plug the USB cable into the phone. The screen will stay black, but your PC should make a connection sound, and the port will appear in QFIL.
- QFIL “Sahara” or “Firehose” Error: This error points to a communication failure. Use a high-quality USB cable, connect directly to a reliable USB 2.0 port on your computer, and ensure no other conflicting mobile drivers are installed.
- AT&T Carrier Firmware: This is official firmware for the AT&T network in the US. After flashing, your device will be restored to this specific software, which will include AT&T branding and pre-installed applications. It will not remove the SIM lock.
FAQs
Q1. My phone is stuck on the AT&T logo. Will this fix it?
Yes. Being stuck on the carrier logo is a “bootloop,” which is a classic software issue. A clean flash of the official stock ROM using this guide is the most reliable way to fix it by completely resetting the operating system.
Q2. Will this unlock my phone from the AT&T network?
No. Flashing the stock firmware restores the phone’s original software, but it does not remove the SIM/network lock put in place by the carrier.
Q3. My phone is extremely slow. Will this help?
Yes. The ZTE Maven 3 is a very basic device. Over time, it can slow down significantly. A full flash using this guide acts as a deep factory reset and will restore the phone to its original performance level.
Q4. What is a QFIL / EDL firmware?
QFIL (Qualcomm Flash Image Loader) is a tool used to flash firmware in EDL (Emergency Download) mode. This is a very low-level mode, a step below fastboot, designed to recover Qualcomm devices from a “hard brick” state where they are otherwise unresponsive.
