[SOLVED] I'm looking for HOMII Xbook Plus repair guide or schematics (free) - Phones & Tablets Forum

Hi,

I'm hoping you can help me out with my HOMII Xbook Plus. 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.

@Umar

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 HOMII Xbook Plus 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://www.ifixit.com/Answers/View/490764/Is+it+possible+to+install+a+sapphire+screen+onto+a+base+model+Watch
Take a look at comment #1210
Also, this : https://www.ifixit.com/Answers/View/906984/How+to+repair+LCD+BACKLIGHT.
You can also check this video starting from minute 6:

The HOMII Xbook Plus 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 HOMII Xbook Plus 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 HOMII Xbook Plus 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 HOMII Xbook Plus 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://www.ifixit.com/Answers/View/876241/My+power+power+button+doesn't+work

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

The SIM ejector hole is always directly adjacent to the SIM tray itself. If inspection and cleaning don't resolve the issue, and you've identified damage to the NFC antenna or its flex cable, replacement is the next step. iPhones (7/7 Plus): Press and hold Volume Down + Power button simultaneously for about 10 seconds. Step 3: Compressed Air (Optional, with caution): If the above steps aren't enough, use very short, controlled bursts of compressed air from about 6-8 inches away. Applying too much paste: This can reduce thermal efficiency and cause mess. Reinstall Components: Systematically reinstall all the components you removed: logic board, battery, speakers, cameras, shields, screws, etc. Before diving into specific shapes, understanding the underlying principles of tip selection is vital: By methodically testing touchscreen response, adjusting display settings, and ensuring proximity and ambient light sensors function correctly, you can optimize your new display for the best possible user experience. Filling Deep Dings (Optional but Recommended for Significant Depressions): Risk of Condensation and Moisture Damage: Introducing a device to extreme cold, then bringing it back to room temperature, carries a risk of condensation forming internally, potentially leading to liquid damage or corrosion. Disassembling the Module (Extremely Advanced): Some camera modules are designed with a removable outer lens element to access the sensor. In this case, a "home button" malfunction might refer to gesture navigation failure or the entire display needing replacement. Open the phone: Follow a specific repair guide for your model to safely open the device. Ensure its pins are clean and tinned (have a thin layer of solder on them). System Instability: Some root apps or tweaks might conflict with each other or with the underlying Android system, leading to crashes, freezes, or unexpected behavior. This makes discoloration much more apparent and helps differentiate it from content-specific rendering issues. The magnetometer measures the strength and direction of magnetic fields in three axes. Apply heat with the hot air station evenly over the chip, following a controlled thermal profile. Analysis: Look for rapid switching between "charging" and "not charging," fluctuations in current/voltage, or temperature warnings that pause charging. Charge the phone immediately after a reset before restoring data or installing apps to see if the problem persists. As you go, gradually peel away more of the protective liner, pressing the gasket firmly into place with your finger or a plastic tool. Dust/Debris Ingress: Gaps created by a damaged bezel can allow dust and moisture to enter the phone, potentially harming internal components. Physical Damage: Under good light, inspect the area where the magnetometer is located. A dust blower or compressed air canister can also be incredibly useful for removing debris. SIM Card Management: Interacting with the SIM card for network authentication. Before attempting any IMEI modification, understand the legal implications in your region. Hot Air Rework Station: Crucial for precisely heating and removing/installing surface-mount components without damaging the board. Connect to PC and Analyze: Connect your phone to a computer via USB in "File Transfer" (MTP) mode. This reaction causes the liquid resin to solidify, or "cure," almost instantly. Once dry, carefully sand down the excess filler using progressively finer grits (starting with 1000-1500) until it is flush with the surrounding frame.

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