[SOLVED] I'm looking for Samsung SM-A505F Galaxy A50 repair guide or schematics (free) - Phones & Tablets Forum

Hi,

I'm hoping you can help me out with my Samsung SM-A505F Galaxy A50. 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.

@Ciro

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-A505F Galaxy A50 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/social-hub-for-galaxy-sii-taiwanese-version.1131830/
Take a look at comment #697
Also, this : https://www.ifixit.com/Answers/View/293893/Display+screen+is+not+working.
You can also check this video starting from minute 4:

The Samsung SM-A505F Galaxy A50 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-A505F Galaxy A50 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-A505F Galaxy A50 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-A505F Galaxy A50 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/802658/system+starts+and+the+crushes

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

The chip (with solder paste) is then heated again, causing the paste to reflow into perfect, shiny solder balls. You may also need to temporarily connect the display assembly if it was disconnected. Visual Confirmation of Damage: If cleaning doesn't help and other components are ruled out, assume physical damage to the port. Once iTunes/Finder detects your iPhone in DFU mode (black screen, "recovery mode" message), you will be given the option to "Restore iPhone." Remove the Faulty Loudspeaker Module: Once all screws and connectors are removed, carefully lift and remove the old loudspeaker module. To ensure the adhesive forms a strong bond, it's highly recommended to apply consistent pressure for several hours (check the adhesive manufacturer's recommendations, usually 2-4 hours). Difficulty During Reassembly: Internal components might not fit correctly, or screws might not align if the spacer is warped or cracked. Trusted Sources: Obtain firmware from the manufacturer's official support site, reputable Android forums (like XDA Developers), or trusted firmware repositories. Before embarking on this repair, gather the following essential tools and materials: Carefully peel or lift the entire sensor flex cable module (which might include the earpiece speaker, ambient light sensor, and proximity sensor) from its adhesive. This guide will provide a comprehensive, step-by-step walkthrough to help you safely replace a cracked or faulty LCD display, restoring your smartphone's visual clarity and interactive capabilities. When to Use: Severely stripped screws where the head is still accessible. Test with a Full-Screen Solid Color: This is the most effective method. If attached to the back cover: This is the most common and simplest scenario. Process: Put the phone into download mode (or equivalent for your device), connect to the computer, and flash the full firmware package. Although you're replacing the motherboard, some procedures might require backing up the "NVRAM" (Non-Volatile Random Access Memory) partition from a donor board of the same model. Magnifying Glass or Microscope: Essential for detailed inspection of tiny components and crevices. Hot Air Rework Station: For removing and replacing integrated micro-components that are too small for a soldering iron alone. Modern smartphone displays are "fully laminated," meaning there are no air gaps between the outer glass (often incorporating the digitizer), the optically clear adhesive (OCA), and the underlying LCD or OLED panel. Logic Board Component Failure: If a new motor doesn't resolve the issue, the problem might be at the logic board level. Power Management IC (PMIC) Fault: In rare cases, the power management integrated circuit on the motherboard might be faulty, leading to incorrect temperature readings or charging control. This external corrosion often indicates internal corrosion as well, which can affect the screen's flex cables or connectors. Use component designators (e.g., U4000) or net names (e.g., VDD_MAIN) to quickly jump to relevant sections. Know Your Model: Research the specific smartphone model you're working on. Among the most crucial are the gyroscope and magnetometer, often integrated into a single Inertial Measurement Unit (IMU) chip. If the phone still fails to charge after a factory reset (before restoring backups or installing new apps), the problem is almost certainly hardware-related. In bright environments, it increases brightness for better visibility, while in dim conditions, it reduces brightness to prevent eye strain and conserve power. An "open loop" (OL) or infinite resistance indicates the inductor's internal winding is broken, which is a common failure mode. Isopropyl Alcohol (IPA - 90%+ pure): Essential for cleaning old adhesive residue from frames and components, and for cleaning corrosion from water-damaged boards. Painter's Tape or Clear Packing Tape: To cover the cracked glass and prevent shards from scattering during removal.

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