[SOLVED] I'm looking for I mobile TV 523 repair guide or schematics (free) - Phones & Tablets Forum

Hi,

I'm hoping you can help me out with my I mobile TV 523. 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.

@Katarzyna

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 I mobile TV 523 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/496196/Touch+ID+stop+working
Take a look at comment #1295
Also, this : https://xdaforums.com/t/q-saurom-kk4-w-ics-theme-battery-life.1496270/.
You can also check this video starting from minute 5:

The I mobile TV 523 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 I mobile TV 523 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 I mobile TV 523 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 I mobile TV 523 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/nexus-6p-stock-rom-on-mate-8.3314542/

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

If you used B-7000 glue, this typically takes several hours, potentially up to 24 hours, for a full bond. Custom ROM: A modified version of Android (e.g., LineageOS, Pixel Experience) developed by third-party communities, often offering features or optimizations not found in stock Android. The level of disassembly required depends on which microphone mesh you're replacing and your phone model. Too little heat will result in cold joints or inability to remove components. Use clamps or rubber bands to apply even pressure during curing if recommended. Type of Liquid: Pure water is less damaging than corrosive liquids like salt water, soda, or urine, which leave conductive and corrosive residues. The term "internal plastic shielding" encompasses a variety of components, each designed for a specific purpose: Does the camera attempt to focus, or does it remain completely unresponsive? Does manually setting the focus point yield better results than automatic focusing? Disconnect the battery as the very first step after opening the device to prevent short circuits. Apply new adhesive strips (if you chose to use them) around the perimeter of the frame or back cover. System Cache Partition: This is a system-wide cache used by the Android OS itself. Look for any signs of corrosion, residue, or discolored water damage indicators inside the device, especially near the digitizer connector or on the screen's flex cables. Corrosion/Damage: Clean any remaining corrosion with IPA and a fiberglass pen if necessary, but be gentle. The associated flex cables and their connectors on the motherboard, which carry touch data to the IC, are also carefully checked for damage, bends, or corrosion. Look for signs of corrosion, which often appear as green, white, or blue powdery residue on the pins or surrounding areas. Component Damage: Tiny chips (resistors, capacitors) can be cracked, missing, or corroded. Excessive Cold: If the phone is very cold, warm it up gradually to room temperature. Locate the battery connector on the motherboard and gently disconnect it using a plastic spudger. Phone Doesn't Detect Headphones: Audio continues to play through the phone's speakers even when headphones are plugged in, or it constantly switches between speaker and headphones. Check Auto-Rotate Settings: Ensure the auto-rotate feature is enabled in the phone's quick settings panel or display settings menu. Severity of Corrosion: Minor, localized corrosion on a few contacts is more treatable than widespread, heavy corrosion under multiple ICs. Debris Ingress: Dust, lint, or other small particles can get under the button or into the connector, interfering with its operation. Manufacturing Defects: Rare, but poor quality control can lead to faulty coils from the factory. Assessing its calibration is key when users experience issues like accidental call interactions or a screen that remains stubbornly black after a call. Look for any patches that appear darker or less luminous than the surrounding areas. Front display removal: Use a suction cup and opening picks after heating the display edges. Precision Screwdriver Set & Pry Tools: For disassembling the smartphone. Damaged Pads: If a via terminates at an exposed pad, check for lifted, scratched, or missing pads. Corrosion: Check for signs of liquid damage or corrosion (green/white residue) on any part of the antenna system or its contact points. This is notoriously known as "Touch Disease" or "Flexgate" in some Apple devices, though often related to display flex, motherboard flex can cause similar.

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