[SOLVED] I'm looking for MOBICEL RX17 repair guide or schematics (free) - Phones & Tablets Forum

Hi,

I'm hoping you can help me out with my MOBICEL RX17. 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.

@Carl

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 MOBICEL RX17 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/q-decent-rpg-game.793204/
Take a look at comment #567
Also, this : https://xdaforums.com/t/notice-any-difference.1190199/.
You can also check this video starting from minute 3:

The MOBICEL RX17 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 MOBICEL RX17 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 MOBICEL RX17 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 MOBICEL RX17 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/373744/Laptop+screen+won't+turn+on.

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

Identify Background Data Usage: Many apps continue to use data in the background even when you're not actively using them. The "System UI isn't responding" error can stem from a variety of causes. System Processes: Pay attention to system processes like "Android System," "Android OS," "Phone idle," "Wi-Fi," "Cell standby." High usage here can point to deeper software or hardware issues. The most critical safety step, immediately upon opening the phone, is to disconnect the battery. Note: Keep track of all screws, noting their sizes and locations, as they can vary. Prepare New Clips: If the new clips are very small, handle them with fine-point tweezers. Excessive heat can cause these layers to delaminate, losing electrical contact between the RAM and the CPU, leading to boot failures. It involves micro-soldering to diagnose and replace the Force Touch controller IC or repair damaged traces on the logic board. Visually inspect: Look for any signs of physical damage to the flex cable itself (creases, tears, burn marks) or to its connector on the logic board (corrosion, bent pins, debris). Apply gentle heat to the outside of the camera lens area on the back cover. If the app installs successfully in Safe Mode, it indicates a conflicting third-party app. If the bracket is bent, broken, or misaligned, it will prevent the button from seating correctly, leading to wobbling. The most common causes for a damaged audio jack are physical trauma (e.g., dropping the phone while headphones are plugged in, forcing an incompatible plug), liquid damage (causing corrosion), or simply wear and tear over time from repeated plugging and unplugging. Isopropyl Alcohol (99% or higher): For cleaning any residual adhesive or grime from the phone's frame. Rattling Sounds: A loosely aligned camera module can vibrate and produce an annoying rattling sound, especially when the haptic engine activates. It should show a specific voltage drop in one direction and an open circuit (no reading) in the reverse. Always disconnect the battery first and avoid direct heat application to it. Once in the correct mode, connect your phone to your computer using the USB cable. Isopropyl Alcohol (IPA) Method: If no thermal camera is available, apply a thin layer of IPA over the suspected area of the motherboard. For tougher smudges, use a small amount of distilled water or a dedicated screen cleaner (never harsh chemicals like window cleaner). Precision Glue (e.g., B7000 or specialized phone adhesive) (Rarely needed): Only if the new button requires a tiny amount of adhesive for seating, but most are friction-fit or held by a bracket. Varies in Severity: The intensity of the burn-in can range from a very subtle, barely noticeable shadow to a distinct, distracting outline. Test the 5GHz connection from various locations within your home or office. Battery Health Apps: Some phones have built-in battery health indicators in settings (e.g., iPhone) or you can use third-party apps (e.g., AccuBattery for Android) to get an estimate of battery health and charge/discharge rates. Features like adjustable temperature, airflow, and different nozzle sizes are invaluable. Ensure the correct mode is selected (e.g., "File transfer / Android Auto" (MTP), "PTP" for photos, "MIDI," or "No data transfer"). Replacing this combo unit requires a delicate approach due to its location at the top of the display and its integration into a sensitive flex cable. In conclusion, repairing or replacing antenna contact points is a precise and often rewarding repair that can significantly improve your smartphone's connectivity and overall performance. Carefully inspect the area around the display connector and the backlight circuit components (driver IC, inductor, diode, capacitors). If this happens, a message will appear indicating that performance management has been applied, with an option to disable it (though doing so might lead to more frequent shutdowns).

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