Brand: ZTE
Category: Cell Phone
Document Type:
Language: EN
Manual for V790
Uploaded: Aug. 9, 2025, 11:59 p.m.
Manual Publish Date: 2012-11-05
1. **Product Overview:** Provides a visual representation and general information about the ZTE V790.
2. **Standard Configuration:** Lists the items included in the sales package: Handset, Battery, Charger, Data cable, User manual.
3. **Specifications:** Details the technical specifications including frequency bands, operating system, dimensions, weight, LCD, camera, battery capacity, external storage, and earphone type.
4. **Main Functions:** Outlines the key capabilities of the phone, such as dual SIM support, SMS/MMS, GPS, Bluetooth, WiFi, FM, media playback, email, web browsing, and application support.
5. **Function Test (NFF Test):** A systematic process to check basic requirements, fault replay, basic functions, call test, and charging test to determine if the phone is NFF (No Fault Found).
6. **Software Download:** Instructions on how to install the necessary drivers and download software using the provided platform, including prerequisites and step-by-step guides.
7. **Troubleshooting:** A comprehensive guide with flowcharts to diagnose and resolve common issues like hanging, automatic switching off, charging failures, USIM card issues, T-Flash card failures, no transmitted/received voice, no ring tone, vibration failure, touch screen/display/camera failures, keypad backlight issues, WiFi/Bluetooth/FM failures, no signal, and no calls out.
8. **Final Test:** Procedures for checking the software version and performing a final function test.
9. **Appendix:** Information on accessing the ZTE After-Sales Technical Support Website for further assistance and documentation.
Troubleshooting and error codes
| Issue | Troubleshooting Steps | Possible Cause |
|---|---|---|
| Hanging | Check battery charge. Check mainboard. Replace housing if battery and mainboard are normal. | Battery issues, Mainboard issues, Housing issues |
| Automatically Switching Off | Check battery status. Check battery connector metal patch. Replace mainboard if other checks pass. | Battery issues, Connector issues, Mainboard issues |
| Charging Failure | Check charger, battery, battery connector metal patches, and system connector. Replace mainboard if other checks pass. | Charger issues, Battery issues, Connector issues, Mainboard issues |
| USIM Card Unidentified | Check USIM card and connector. Clean or replace USIM card. Rectify metal patch or replace mainboard. | USIM card issues, Connector issues, Mainboard issues |
| T-Flash Card Failure | Check T-Flash card. Replace mainboard if card is normal. | T-Flash card issues, Mainboard issues |
| No Transmitted Voice | Check MIC. Replace mainboard if MIC is normal. | MIC issues, Mainboard issues |
| No Received Voice | Turn up volume. Check receiver. Replace mainboard if receiver is normal. | Volume setting issues, Receiver issues, Mainboard issues |
| No Ring Tone | Turn up volume. Check speaker. Replace mainboard if speaker is normal. | Volume setting issues, Speaker issues, Mainboard issues |
| Vibration Failure | Adjust vibration mode. Check motor. Replace mainboard if motor is normal. | Vibration mode settings, Motor issues, Mainboard issues |
| Touch screen failure | Check FPC connection. Check touch screen. Replace mainboard if touch screen is normal. | FPC connection issues, Touch screen issues, Mainboard issues |
| Display Failure | Check LCD FPC connection. Check LCD. Replace mainboard if LCD is normal. | LCD FPC connection issues, LCD issues, Mainboard issues |
| Camera Failure | Check camera connection. Check camera. Replace mainboard if camera is normal. | Camera connection issues, Camera issues, Mainboard issues |
| Keypad Backlight Failure | Replace mainboard. | Mainboard issues |
| WiFi/Bluetooth/FM Failure | Rectify antenna contacts or replace back cover. Replace mainboard. | Antenna issues, Back cover issues, Mainboard issues |
| No Signal | Check USIM card and antenna. Replace mainboard if both are normal. | USIM card issues, Antenna issues, Mainboard issues |
| No Calls Out | Cancel call limit. Reinstall USIM card. Replace back cover. Replace mainboard. | Call limit settings, USIM card issues, Back cover issues, Mainboard issues |