[SOLVED] I'm looking for LG Jil Sander Mobile repair guide or schematics (free) - Phones & Tablets Forum

Hi,

I'm hoping you can help me out with my LG Jil Sander Mobile. 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.

@Bradley

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 Jil Sander Mobile 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/google-assistant-voice-model.3710380/
Take a look at comment #863
Also, this : https://xdaforums.com/t/upgrading-to-new-rom-jamin.268561/.
You can also check this video starting from minute 5:

The LG Jil Sander Mobile 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 Jil Sander Mobile 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 Jil Sander Mobile 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 Jil Sander Mobile 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/how-good-is-the-camera.941495/

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

Carefully place the new front-facing camera module into the housing, ensuring it sits perfectly. Sharp Scalpel/Fiberglass Pen/Scratch Tool: For carefully scraping away the solder mask to expose the bare copper of the trace. In conclusion, inspecting smartphone antenna contact points is a detailed, meticulous process that plays a crucial role in troubleshooting wireless connectivity problems. Identify VBAT/VCC_MAIN: Trace the positive terminal of the battery connector. Begin with the least invasive steps to rule out common software or user-related issues. The modern smartphone is a marvel of miniaturization and complex engineering, packed with multiple antennas to facilitate a multitude of wireless communication standards. Anti-Static Gloves: To protect your hands and prevent static discharge. For older devices with weaker adhesives or LCD screens: Heat plate is usually adequate and more cost-effective. Over time, or due to manufacturing inconsistencies, this thermal paste can degrade, dry out, crack, or be poorly applied from the factory, leading to reduced thermal efficiency. Exercise greater caution on plastic frames to avoid scratching or gouging. Before you even consider opening your smartphone, a few critical preparations and safety precautions must be observed. In the complex ecosystem of a smartphone, every tiny component plays a critical role, and the antenna contact springs are no exception. Entry-level thermal cameras, often smartphone attachments or handheld units, offer sufficient resolution for general board scanning. In some less common scenarios, if the device heavily relies on the magnetometer for screen auto-rotation decisions, this function could also be impacted, though this is more typically governed by the accelerometer and gyroscope. If the glass is heavily fragmented, use a very fine-tipped metal pry tool (like a thin razor blade or hobby knife) with extreme caution to create a tiny gap between the lens glass and the phone's frame. Reconnect all flex cables, ensuring they click firmly into their connectors. It's often integrated into the display assembly, sitting either directly on top of or within the LCD/OLED panel. Super Glue (Cyanoacrylate adhesive - CA Glue): Use with EXTREME CAUTION. Be extremely cautious of flex cables that connect these panels to the main board; ripping them can cause further damage. This indicates a mismatch between the component's serial number and what the device expects. Ensure your phone's battery is adequately charged to prevent it from dying during troubleshooting steps or system updates. Replacement internal plastic vibration motor mount (sometimes sold with the motor, sometimes a separate frame part) Toggle DC Dimming: If the phone has a "DC Dimming" or "Anti-Flicker" setting (usually in Display or Developer Options), enable/disable it to see if it affects the flicker. Some smartphone designs integrate the camera lens ring into the entire back cover, a camera module bracket, or the internal mid-frame. This guide will introduce the basics of using a multimeter for fundamental smartphone circuit board diagnostics. It's primarily used for flashing custom recoveries, rooting devices, updating firmware, or unlocking the bootloader. Such issues typically require professional repair, involving either replacement of the sensor chip or the entire motherboard, depending on the phone's design and the severity of the damage. Repair: Involves intricate trace repair, component replacement, and cleaning. Too little heat will result in cold joints or inability to remove components. Factory Reset: As a last resort for software issues, a factory reset can clear out any accumulated software glitches or conflicting settings.

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