[SOLVED] I'm looking for BBK Vivo Y3s repair guide or schematics (free) - Phones & Tablets Forum

Hi,

I'm hoping you can help me out with my BBK Vivo Y3s. 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.

@Bonnie

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 BBK Vivo Y3s 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/demonstration-video-play-arc-neo-all-newer.1076519/
Take a look at comment #661
Also, this : https://xdaforums.com/t/huawei-g7-bootloop-help-please.3415768/.
You can also check this video starting from minute 6:

The BBK Vivo Y3s 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 BBK Vivo Y3s 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 BBK Vivo Y3s 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 BBK Vivo Y3s 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/new-to-s8-how-to-remove-keyboard-icon-in-navbar.3627259/

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

Physical Damage: Drops or impacts can dislodge a sensor module or flex cable. Check the display connector for bent pins, debris, or corrosion, which could short lines or prevent proper signal transmission. However, assessing their accuracy is not always straightforward, as various factors can influence their state and interpretation. If using clamps, ensure the pressure is even and not excessive, which could damage the display. Manufacturers sometimes release updates that include audio driver optimizations. They should be shiny, well-formed, and completely connecting the capacitor to both pads, without any bridges to adjacent components. Visual Inspection: Eject the SIM tray and inspect the internal slot with a flashlight for dust, lint, or bent internal pins. It will be connected to the logic board via a small ZIF (Zero Insertion Force) connector or a similar flex cable connector. Install the New Motherboard: Carefully place the new motherboard into the phone's frame, aligning it perfectly with the screw holes and standoffs. Patience and Magnification: Work slowly and use a magnifying glass or microscope. (Requires opening the device, which voids warranty and requires technical skills). Preventing battery connector pin issues primarily revolves around careful handling and maintenance. When an "in-phase" sound is played through two correctly phased speakers, it should sound full and possibly centered. This involves downloading the official firmware for your specific phone model and using a manufacturer-specific tool (like Odin for Samsung, MiFlash for Xiaomi, or Fastboot for Google Pixel/generic Android) to reinstall the entire operating system. Once you've identified and replaced the faulty component (speaker, flex cable), carefully reassemble the phone, ensuring all flex cables are properly connected and screws are in their correct places. In conclusion, test points are the unsung heroes of smartphone micro-repair. Hard Boot Loop (or endless rebooting): The phone only shows the initial manufacturer logo for a very short period, or perhaps just vibrates, before restarting. See if the SD card appears there, even if it's unallocated or shows as "RAW." If it doesn't appear at all, the card is likely dead. It requires sustained, even heat to melt all perimeter solder joints simultaneously. For example, if red pixels are more degraded in a certain area, a green or blue background might make that area appear slightly purplish or yellowish. Reconnect the battery and test the microphone function (make calls, record audio, test voice assistants) before fully reassembling the device. Turn Off Your Phone: This prevents accidental touches and helps you see dust better against a black screen. It functions as a dedicated, highly specialized processor, distinct from the phone's main Application Processor (CPU). With the right tools, a methodical approach, and a lot of patience, it's a very achievable fix that can bring a non-functional device back to life.9. Some hardware failures are "silent" (e.g., an intermittently failing solder joint that doesn't always throw an error) or occur at such a low level that the OS can't log them. Understanding how to diagnose and repair these contact points is vital for restoring a smartphone's full connectivity. Plastics: Genuine plastic moldings are usually clean, precise, and free of burrs or uneven edges. Scenario: The physical button is mushy, broken, or not clicking, but the Touch ID flex cable (the part with the fingerprint sensor) is intact and undamaged. Responsibility: The technician assumes responsibility for the outcome of the flashing process and its immediate aftermath. Components Don't Fit: If you built up too much material, it might interfere with other components.

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