[SOLVED] I'm looking for LG Optimus L2 II repair guide or schematics (free) - Phones & Tablets Forum

Hi,

I'm hoping you can help me out with my LG Optimus L2 II. 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.

@Olivia

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 LG Optimus L2 II 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/android-market-2-phones-1-account.718459/
Take a look at comment #309
Also, this : https://xdaforums.com/t/official-stock-firmware-for-moto-x-play-xt1564-lra-5-1-1.3311434/.
You can also check this video starting from minute 3:

The LG Optimus L2 II 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 LG Optimus L2 II 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 LG Optimus L2 II 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 LG Optimus L2 II 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/479669/Wifi:+No+Hardware+Installed

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

Place one probe on the VBUS pin and the other on a known ground point (e.g., the metal casing of the USB port, a screw hole). Location: Which specific LCIs are tripped? One in the SIM slot only? Or multiple on the motherboard and flex cables? The more internal and numerous the tripped LCIs, the higher the confidence in significant water damage. A professional can accurately diagnose whether it's a loose connector, a faulty antenna, or a complete Wi-Fi IC failure, and advise on the most cost-effective solution.3. Laggy or delayed touch response can also be interpreted as a calibration issue, though it's often more related to system performance. Smartphones are packed with an array of sensors that enable many of their intelligent features, from automatic screen rotation to precise navigation. Plastic Spudgers and Guitar Picks: For large, softened blobs, a thin, rigid plastic spudger or a guitar pick can be used to carefully lift and peel away the softened glue. OS updates often include bug fixes and performance improvements that can address such issues. If no obvious visual damage is present, the multimeter becomes your primary tool. Reinstall Pentalobe Screws: Fasten the two Pentalobe screws at the bottom of the iPhone. Software updates often include bug fixes and performance improvements. For most users, seeking professional help from a reputable repair shop is often the safest and most reliable option.3. Severe Performance Issues: If the phone is excessively slow, laggy, or frequently freezes, a factory reset can often resolve software-related bottlenecks. For experienced technicians, it helps in tracking complex, multi-stage repairs, ensuring no steps are missed or components overlooked. Sufficient Storage Space: Ensure you have enough space in your cloud account or on your local computer/external drive for the backup. Adhesive: If you removed an adhesive-backed back cover or screen, apply new pre-cut adhesive strips or a thin bead of B-7000/T-7000 adhesive to secure it. If the microphone is a surface-mounted component (MEMS mic) directly on the logic board: This requires micro-soldering. Made of soft plastic, they allow you to pry open seams and disconnect connectors without scratching or shorting components. Board Damage: High heat, improper underfill removal, or prying can easily damage the multi-layered PCB, rendering it irreparable. If your phone boots successfully into Safe Mode, it strongly indicates a recently installed app is causing the conflict. Visual Movement: If you open the camera app and gently shake the phone, you might see the image "jump" or not stabilize correctly. It’s absolutely critical to start with the lowest possible current limit and gradually increase it. Access: Can you successfully enter Recovery Mode or Fastboot Mode? If not, the corruption is severe (possibly bootloader damage) or there's a hardware fault. While your phone might support individual bands, if it doesn't support the specific CA combinations your carrier uses, you might not get the absolute fastest speeds. Symptoms of Being Stuck: The phone constantly boots into Safe Mode, and there's usually a "Safe Mode" watermark visible on the screen. Excessive heat can damage surrounding surface-mount devices (SMDs), ICs underneath the shield, or even warp the mainboard. Regulates Charging Current/Voltage: Ensures the battery receives the correct current and voltage from the charger to prevent overcharging or damage. Operating system bugs or recent updates, on both phone and computer, can sometimes introduce instabilities in the USB stack. If software troubleshooting doesn't fix the issue, the vibration motor itself or its connection to the motherboard is likely at fault. Software Issues: Boot loops, stuck on logo, unresponsive OS, system crashes, failed software updates, "bricked" devices. Suction Cup: Often used to assist in carefully lifting the display assembly, especially for phones that open from the front.

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