[SOLVED] I'm looking for Samsung SM-G611MTDS Galaxy J7 repair guide or schematics (free) - Phones & Tablets Forum

Hi,

I'm hoping you can help me out with my Samsung SM-G611MTDS Galaxy J7. 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.

@Alejandro

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 Samsung SM-G611MTDS Galaxy J7 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-mms-problem.2158347/
Take a look at comment #609
Also, this : https://www.ifixit.com/Answers/View/519828/Where+do+I+start+with+this+DSi+repair-rebuild.
You can also check this video starting from minute 3:

The Samsung SM-G611MTDS Galaxy J7 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 Samsung SM-G611MTDS Galaxy J7 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 Samsung SM-G611MTDS Galaxy J7 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 Samsung SM-G611MTDS Galaxy J7 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/Guide/HP+ProBook+450+G4+Hard+Drive+Replacement/130555

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

Power off the phone, apply heat to soften adhesive, and carefully open the phone (usually the back cover or screen). Attempting repairs with inadequate or incorrect tools can lead to frustration, wasted time, and, most critically, irreparable damage to delicate and expensive components. Microphones vary in size, pinout, and internal acoustic properties (e.g., analog vs. Prepare the New Mesh: If your new mesh comes with a protective film over the adhesive, carefully peel it off using tweezers. Use a soft brush, a can of compressed air (from a distance), or a toothpick (very gently) to clear them. Check underneath for debris: If the tape was applied over dust or foreign material, it will not adhere properly and may have compromised shielding. For Corrosion (Advanced): If corrosion is present, a tiny amount of 99% isopropyl alcohol (IPA) applied with a non-conductive swab or brush (after debris removal and with the battery disconnected) can help. If the flickering stops or significantly reduces in Safe Mode, it strongly indicates that a recently installed or an existing third-party application is the root cause. If the original flex cable is irreparably damaged, Face ID will, regrettably, remain non-functional.## 8. Reinstall Components: Reinstall all mid-frames, shields, and other components in reverse order, ensuring all screws are in their correct positions. Clean with IPA: Once all pads are clean and smooth, thoroughly clean the area with isopropyl alcohol to remove all flux residue. Backlight Circuit Failure: The LCD or OLED panel is receiving data but has no illumination. Check all areas of the screen, perform multi-touch gestures, and verify responsiveness. Repeated Connection/Disconnection: While designed for a certain number of cycles, excessive or rough handling can wear out the pins. If shorted, it will draw excessive current and the IC may fail or protectively shut down. No Display, But Phone is On: The phone vibrates, makes sounds, and responds to touch, but the screen remains completely black. Tiny Component Size: Both the TP IC and its solder pads are minuscule, requiring high magnification and fine-tipped tools. Restoring is equivalent to a factory reset and full OS reinstallation. PCB Preheater: Absolutely critical for uniform heating of the board from below, minimizing thermal shock and warping. Using very fine-tipped jeweler's pliers or micro-vise grips, carefully clamp onto the very edges of the screw head. Apply gentle pressure around the edges of the screen and on the back of the phone. Replacing the audio codec chip on a smartphone is an advanced, micro-soldering repair that falls squarely into the realm of professional mobile phone technicians. It's crucial to understand that achieving factory-level water resistance in a DIY setting is extremely challenging, but restoring splash resistance is often achievable. Loudspeaker Assembly: The loudspeaker module is often situated directly over the charging port daughterboard. Slide the plastic tool further under the battery, slowly working your way along an edge. Prying Method (with caution): If there are no pull tabs, or if they broke, you'll need to carefully pry the battery. Start with a simple restart of your smartphone, which can often resolve temporary software conflicts. If your new loudspeaker has pre-applied adhesive, peel off the protective backing and press it gently into place. Unfortunately, daily use often subjects this frame to nicks, dings, and scratches, marring its pristine appearance. Optional: If your phone uses thermal pads instead of or in addition to paste, you might need replacement thermal pads of the correct thickness.

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