[SOLVED] I'm looking for SENSEIT L105 repair guide or schematics (free) - Phones & Tablets Forum

Hi,

I'm hoping you can help me out with my SENSEIT L105. 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.

@Nico

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 SENSEIT L105 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/Guide/Kodak+EasyShare+V570+Case+Replacement/168197
Take a look at comment #573
Also, this : https://www.ifixit.com/Answers/View/325462/Faulty+bluetooth.+Where+is+BT+module.
You can also check this video starting from minute 10:

The SENSEIT L105 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 SENSEIT L105 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 SENSEIT L105 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 SENSEIT L105 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/phone-upgrade.3393024/

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

Is it swollen? Is there any visible corrosion or liquid residue on or around it? Note any damage. Using ESD-safe plastic tweezers or a spudger, carefully pry up the small snap-on connectors from their sockets on the logic board and the antenna module/flex. Expected Reading: There should be no continuity (OL) between these pins. For example, a spike to 50-100mA then drop might indicate an early CPU failure. Used to create a vacuum seal on the display or back glass, allowing you to pull and create a gap for your opening picks. ESD-Safe Mat and Wrist Strap: To protect sensitive electronic components from static discharge. Use a plastic spudger or scraper to remove all old adhesive residue from the display bezel. If the coaxial connector is loose, gently press it down to ensure it's firmly seated. The goal is always to remove the faulty IC without damaging the motherboard, adjacent components, or the IC itself if it needs to be reballed. Repair: Component replacement, trace repair, or micro-soldering remediation of liquid damage. Cooling and Inspection: Remove the hot air and allow the board to cool naturally. Smartphone logic board contamination refers to the presence of unwanted substances on the device's main circuit board, most commonly liquid (water, soda, sweat), but also dust, metallic particles, or corrosive chemicals. It is critical to power off the device and disconnect the battery before beginning any internal inspection to prevent short circuits or electrical damage. Without these, accessing the decrypted user data is designed to be extraordinarily difficult, even for the device owner if they forget their passcode, let alone a third-party repair technician. Ensure its orientation (pin 1 marker, usually a dot or notch) matches the orientation of the original IC on the board. Select an old, sacrificial screwdriver bit that fits the stripped screw as best as possible. Isolation: While monitoring the current, you can sometimes carefully remove components (e.g., camera modules, charging port flex, display) one by one (if safe and practical) to see if the current draw drops, helping to isolate the faulty part. These are typically connected to the main logic board via tiny coaxial cables or direct contact pins. Regular Updates: Keep your OS and apps updated, as updates often include bug fixes for display-related issues. Carefully slide the pick around the perimeter, continually applying heat, until the rear glass can be lifted. Oscilloscope Use: For intermittent issues or noise problems, an oscilloscope can be used to observe the stability and ripple on power rails, identifying transient drops or excessive noise that a multimeter can't catch. Some dongles require external power; ensure it's connected if applicable. If the problem persists, the issue is on the logic board, not the flex. Broken Traces: Fine lines (traces) leading from the pad that are cracked or severed. If the earpiece is part of a flex cable, and the resistance test on the earpiece itself passes, check the continuity of the flex cable's traces that lead to the earpiece. Error Messages: Note any specific error messages, especially during boot or update attempts. Damaged Microphone Component: A physical defect or internal short circuit within the tiny microphone (MEMS mic) itself can cause it to report constant activity. Cable Ends: Inspect the connectors on your USB cables for damage, bent pins, or signs of stress. This typically involves applying heat to soften adhesive and prying open the display assembly or back cover. If the eMMC chip is encapsulated in underfill (a hard epoxy resin used for mechanical stability), this must be carefully removed.

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