[SOLVED] I'm looking for SNEXIAN Fire 105 repair guide or schematics (free) - Phones & Tablets Forum

Hi,

I'm hoping you can help me out with my SNEXIAN Fire 105. It's started acting up, and I'm looking for a detailed service manual with boardviews and schematics to properly diagnose and repair it. I need to take precise voltage measurements around the board, so having the right documentation would be very helpful.

Thanks in advance for your help.

Selected Answer

I actually found that service manual on a tech Discord server a while back. A really helpful member there shared a direct link to their blog and I've saved it. I'm happy to pass it along here. Hopefully, these boardviews and schematics help you fix your phone, just like they got me through my repair. Looks like we have the same model.

@Marine

Absolute legend! That's exactly the info I was searching for. This is going to save me so much time probing in the dark. Seriously, thanks a ton for sharing the link!

Hi there,

I also have the SNEXIAN Fire 105 and just downloaded the manual you shared. I'm pretty new to board-level phone repair, and this is a bit intimidating with all the tiny test points and the schematics. Could you point me in the right direction on how to start troubleshooting this ? Any advice on the first few things I should check would be a massive help.

Thanks so much for your time

General advices: start by checking the voltage at the battery connector on the board. With a known-good battery connected, you should see a steady voltage between 3.7V and 4.2V. After that, a great next step is to check the main power management IC (PMIC) for shorts. Using your multimeter in diode mode, check for shorts on the large input capacitors surrounding the PMIC.

Here are a few useful references for troubleshooting your device:
https://xdaforums.com/t/q-switch-off-button.1442574/
Take a look at comment #1423
Also, this : https://xdaforums.com/t/battery-not-charging-overnight.1889944/.
You can also check this video starting from minute 7:

The SNEXIAN Fire 105 service manual and boardviews from the link above were exactly what I've been searching for. I couldn't find a complete, free copy anywhere else. Seriously, thank you for sharing this you're a lifesaver!

Hi everyone, I'm working on a SNEXIAN Fire 105 with a no power issue and need some guidance with my measurements.
I'm detecting 3.3V on the VREG_MAIN line (pin 1 of the PMIC), which looks good, but I'm getting 0V on the VDD_CPU line (pin 8) where the schematics indicate I should see about 0.9V.
Since this is a core voltage for the application processor, could this missing rail be why the device shows no signs of life?
What's the best procedure to diagnose this further? Should I check for shorts on the CPU rail first, or look at the PMIC's enable signals?
I've already verified the main 3.3V and 1.8V power rails are present and stable.

My SNEXIAN Fire 105 was working perfectly until yesterday when it suddenly went completely dead. Now it won't respond to the power button, doesn't vibrate, and shows no signs of life even when connected to a charger. I'm worried there might be a serious issue.

I have a decent multimeter, a basic soldering iron, and a healthy dose of patience. While I've successfully replaced iPhone batteries and charging ports, this will be my first attempt at actual diagnosis. The sheer density of BGA chips and microscopic components is honestly a bit overwhelming.

I'm particularly curious about the alcohol trick I've seen online where you apply isopropyl to the board and look for evaporation hotspots to locate shorts. Is this actually a reliable method for beginners, or are there better approaches I should try first with just a multimeter?

I learned this lesson the hard way last month with mine, it was declared "dead" by two different shops. The phone showed absolutely no signs of life - no charging indicator, no vibration, nothing. Before diving into complex board work, I decided to try one more basic test: wireless charging.

To my complete surprise, it actually heated up on the charging pad! This single discovery completely changed my diagnostic path. It turned out the issue wasn't with the main board or processor, but with the notoriously fragile USB-C port that had failed completely. A $15 replacement part and some careful soldering brought it back to life.

The moral? Always exhaust every external testing method before opening the device. Test wireless charging if available, try different charging methods, and don't assume the worst case scenario. Sometimes the most "dead" devices have the simplest solutions hiding in plain sight.

I suspect my issue might be related to that cheap, third-party fast charger I used at the airport last week... Now the device gets extremely hot during charging, the screen flickers at low brightness, and sometimes it randomly shuts down at 30% battery. Could this have damaged the power management IC or battery calibration?

If your SNEXIAN Fire 105 starts acting up, random reboots, fast battery drain, or connectivity issues, there are several diagnostic steps you can take before assuming the worst:

• Check your charging habits: Using poor-quality chargers or wireless pads can gradually damage your battery and charging circuit, leading to unpredictable behavior.
• Inspect the physical components: A slightly damaged charging port, worn battery, or even accumulated pocket lint can cause issues that seem like major hardware failures.
• Monitor temperature patterns: If your phone gets unusually hot during specific tasks (like camera use or gaming), it could point to a failing component rather than a software issue.
• Use diagnostic tools wisely: Ampere for battery health, phone diagnostic codes (*#0*# on many models), and a thermal camera can reveal problems without opening the device.
• Know when to stop: If you see liquid damage indicators tripped or smell burnt electronics, it's time to consult a professional before causing irreversible damage.

Also visit this link it may help : https://xdaforums.com/t/battery-goes-dead-after-a-day-or-two-of-standby-case-issue.3126180/

Here's what I discovered on forums and technical databases:

Insufficient Storage Space: If your phone doesn't have enough free storage, the installation process can fail due to lack of space for the app and its temporary files. SIM Card/Slot Issues: While primarily causing "No SIM," a faulty SIM or dirty slot can sometimes contribute to unstable network registration. Use a suction cup and prying tools to carefully separate the back panel from the frame. Compare this to a video recording (which often uses a different mic) or a speakerphone call (which might also use a different mic). Clips/Latches: Many devices use a combination of clips and adhesive, or just clips, to secure the housing once screws are removed. Choose Phone Cases Wisely: While protection is important, opt for cases with good ventilation or those made of heat-dissipating materials. If the proximity sensor works correctly in Safe Mode, a third-party application might be interfering with sensor readings or system processes. Using a plastic spudger, carefully pry up the battery's flex cable connector from its socket on the logic board to cut power. Accessibility Features: Settings designed to help users with visual impairments (e.g., color inversion, color correction, grayscale mode) can drastically alter the display. They are relatively easy to remove with solvents, making future repairs possible. Alternatively, if the button is permanently attached to the frame but wobbly, and you can access its internal connection point, a tiny drop of adhesive (like B-7000) applied very carefully to the contact points (not the moving parts of the switch) can sometimes help stabilize it. Button Actuator: Ensure the external button cap properly aligns with and presses the internal tactile switch. A blocked microphone can sometimes be misdiagnosed as a speaker issue, so it's worth a brief mention. Interpretation: If performance drastically improves immediately after a factory reset, the issue was likely software corruption, excessive fragmentation, or a rogue app. The integrity of antenna contact springs can be compromised in several ways. Once it settles, continue heating for a few more seconds to ensure all solder balls/pins are fully reflowed. This is a complex repair requiring specialized tools and expertise, usually involving micro-soldering, and is beyond the scope of a typical DIY fix. Bricking refers to a state where a smartphone fails to boot or operate normally. Use a strong, plastic-compatible epoxy or plastic cement to glue the salvaged anchor into position. Logic Board Information: Baseband version, serial numbers of various components, crash logs that can point to IC failures. By meticulously grounding yourself, your tools, and your workspace, you ensure that the invisible threat of static electricity does not undermine your efforts, leading to more reliable repairs and greater longevity for the delicate devices we depend on daily.8. This guide provides general steps; always refer to a device-specific repair guide or video tutorial for your exact phone model, as disassembly procedures can vary significantly. If they are, power off, disconnect the battery, and proceed with full reassembly. Clean Speaker Grilles: This is a very common cause of muffled or no sound. Severe Corrosion: May require ultrasonic cleaning or more aggressive chemical treatment, which is typically done by professional board repair specialists. Write/Read Errors: You might encounter explicit error messages from the system or apps indicating problems with reading from or writing to storage. For iPhones, the display assembly opens from right to left like a book. Fine-point tweezers are indispensable for handling tiny screws, brackets, and delicate ribbon cables. Location Varies: The volume button flex cable's location differs significantly between models. (Optional but highly recommended for advanced repairs) Microscope, soldering station, schematics for your specific phone model.

@Heidi, Not sure what you're trying to say but ok :)