[SOLVED] I'm looking for Xiaomi Redmi A2 Top repair guide or schematics (free) - Phones & Tablets Forum

Hi,

I'm hoping you can help me out with my Xiaomi Redmi A2 Top. 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.

@Lia

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 Xiaomi Redmi A2 Top 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/344038/Do+I+need+to+download+the+SoundStage+app+to+use+the+speaker
Take a look at comment #1092
Also, this : https://xdaforums.com/t/wm2005-working-smartphone-programs-list.239344/.
You can also check this video starting from minute 5:

The Xiaomi Redmi A2 Top 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 Xiaomi Redmi A2 Top 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 Xiaomi Redmi A2 Top 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 Xiaomi Redmi A2 Top 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/closed-guide-how-to-root-infinix-hot-11s-x6812-x6812b.4444717/

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

Step 2: Multimeter Resistance Checks (Power Off, Battery Disconnected) Disconnect the Battery: Once the phone is open, immediately locate and disconnect the battery connector. Avoid Data Copying: Do not copy any customer data unless specifically requested and consented to for a data recovery service. Use a plastic toothpick or a non-metallic dental pick very gently to clear out compacted lint from the charging port. The gyroscope is one of the unsung heroes among a smartphone's suite of sensors, playing a critical role in enabling advanced motion-based functionalities. While primarily for customization, its backup/restore features are invaluable for repair. Visual Inspection: Carefully inspect the camera module(s) and their flex cables for any visible damage: tears, creases, corrosion, or bent pins on the connector. Video Recording Lacks Audio: Videos recorded with the camera have no sound. Physical Damage: The card itself or the phone's SD card slot can suffer physical damage from drops, liquid exposure, or inserting the card incorrectly. Regular Gentle Cleaning: Periodically use a soft, dry brush to gently clean the microphone mesh area to prevent lint buildup. As a last resort for software issues, a factory reset (after backing up data) can rule out deep software corruption. Analyzing smartphone RAM-related malfunctions starts by eliminating software and resource management issues. Analyzing these failures requires a systematic approach, distinguishing between display assembly issues, backlight driver circuit problems, and motherboard component faults. Locate the Hall Sensor: Use the phone's service manual or schematics/boardview software to precisely locate the Hall sensor IC on the logic board or its associated flex cable. Tweezers (Blunt and Fine-Point): Useful for peeling off stubborn strips or picking out small bits of residue. Locate the battery connector on the motherboard and use a plastic spudger to carefully pry it upwards and disconnect it. While these might help with temporary image retention by exercising all pixels, they cannot reverse physical burn-in. Status Bar Icons: Battery indicators, Wi-Fi symbols, network bars, and clock displays often remain static at the top of the screen. Clear Camera App Cache: Go to Settings -> Apps -> Camera -> Storage -> Clear Cache (Android). Install the new, compatible volume rocker flex cable assembly in its place, ensuring it's properly aligned and all connections are secure. Corroded LCD connector: As with physical damage, corrosion on pins can prevent power from reaching the display. Charging Port and Flex Cable: A faulty charging port or its associated flex cable can cause abnormal current draw during charging, leading to overheating, even when the phone isn't actively charging but just connected. Remove these screws and carefully pry off the shields with a plastic spudger. This guide is for informational purposes only, addressing the technical challenges of preserving or restoring an original, legitimate IMEI in specific, legally permissible repair scenarios, primarily involving the repair of the original board or the physical transfer of IMEI-holding components. Heat the Edges: Using your heat gun or hair dryer on a low-to-medium setting, gently warm the edges of the back cover. Remove Magnetic Accessories: If using a magnetic phone case or holder, remove it and retest the sensors. With a clean, pre-tinned soldering iron tip, add a small amount of fresh solder wire to the pads. Physical Impact: A drop or blunt force trauma can crack the plastic housing of the connector, break its internal pins, or even detach the entire connector from its solder pads on the motherboard. New Adhesive: Always use fresh, high-quality adhesive for re-sealing screens or back covers if the phone was designed with it, especially for water resistance. Crucially: Look for metallic foreign objects (e.g., paper clips, staples, foil) that could be shorting the VBUS pin to ground or other pins.

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