[SOLVED] I'm looking for LESIA K5 repair guide or schematics (free) - Phones & Tablets Forum

Hi,

I'm hoping you can help me out with my LESIA K5. 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.

@Leila

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 LESIA K5 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/47535/Can+I+swap+out+Hard+Drive+from+old+MacBook+into+new+MacBook
Take a look at comment #1227
Also, this : https://www.ifixit.com/Answers/View/388148/Grey+Screen+no+reaction.
You can also check this video starting from minute 2:

The LESIA K5 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 LESIA K5 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 LESIA K5 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 LESIA K5 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/912043/Ordered+replacement+battery+which+physically+fits+but+connector+is+bad

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

Internally, there might be LDIs on the logic board itself, near the battery, or under the screen. Taking clear, detailed photographs at each stage of disassembly is an invaluable practice, serving as a visual map for reassembly, particularly for correctly identifying screw locations and bracket orientations. Fine-Tip Tweezers: Essential for handling tiny screws, springs, small connectors, and delicate flex cables. Be extremely cautious not to insert the tool too deeply, as you could damage internal flex cables (especially for the display). Dullness or graininess: Compared to shiny, smooth solder, this can suggest a poor connection. Trying to replace just the tiny ALS component itself is extremely difficult and usually not practical. Gentle Tapping: Using a small rubber mallet or a soft-faced hammer, gently tap the high spot. This requires referring to the boardview to identify where traces should connect. Noise Varying with Phone Activity: The static increases in volume or changes character when the screen turns on, during data transfer (Wi-Fi/cellular), when the processor is under heavy load (e.g., during gaming), or when charging. Slow or Unreliable Mobile Data: Data connectivity can be intermittent or extremely slow, particularly for uploads. Reduced Thermal Stress: Protects sensitive components and prevents PCB damage. If one of these deeply embedded components fails, or if the interposer connection itself is damaged (e.g., due to drops causing fractured solder balls), board separation becomes the only way to access and repair the fault. Initial Power-Up: Carefully connect the battery and power on the device. Incorrectly Seating Connectors: FPC connectors are tiny and require precise alignment. While ethically complex and often illegal for non-owner devices, advanced tools can sometimes interact with these areas. Check S Pen Settings: Navigate to your phone's S Pen settings (usually under Advanced Features or specific S Pen menu). Lay out components systematically, perhaps on a magnetic mat, to remember their placement. It is a procedure fraught with challenges and high risk, demanding specialized equipment, profound knowledge of thermal dynamics, and exceptional dexterity. Always start with software-based solutions, as they are less invasive and often resolve the problem. There is no simple fix for this without specialized equipment or motherboard repair to "re-pair" a new sensor. Microfiber Cloths/Lint-Free Wipes: For wiping away dissolved adhesive and cleaning surfaces. Resistance between Other Pins: Briefly check resistance between VBUS and data pins (D+/D-) and between data pins themselves. Restart the Phone: A full reboot can often resolve temporary software glitches that might be affecting microphone performance. Charging System Malfunction: Issues with the charging IC or battery in that specific region. Back panel removal: Once heated, attach a suction cup near the bottom edge of the back panel. Microscope: Indispensable for inspecting tiny RF components and performing micro-soldering. For this repair, we assume the display itself is not damaged and only the surrounding plastic frame needs replacement. If all software avenues are exhausted, the problem is likely hardware-related. Carefully position the new headphone jack assembly into its designated slot. The flex cable itself should be free of tears or sharp creases near the motor, as this can impede vibration transfer or damage the internal wiring.

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