[SOLVED] I'm looking for DAHUA DA68 repair guide or schematics (free) - Phones & Tablets Forum

Hi,

I'm hoping you can help me out with my DAHUA DA68. 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.

@Kemal

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 DAHUA DA68 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/Answers/View/623330/USB+C+Dead,+USB+Accessories+Disabled.
Take a look at comment #1201
Also, this : https://xdaforums.com/t/kindly-help-out-i-cant-upgrade-my-radio-rom.379205/.
You can also check this video starting from minute 9:

The DAHUA DA68 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 DAHUA DA68 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 DAHUA DA68 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 DAHUA DA68 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/536044/Rear+brake+replacement+tools

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

While this is not a definitive test for water resistance, it indicates proper assembly. Once cured, use a very small drill bit (hand-held pin vise recommended for control) to carefully drill a new pilot hole, slightly smaller than the original screw, through the cured epoxy. A DC power supply allows a technician to power the logic board directly without the internal battery. Swelling (Bulging): This is a critical physical indicator and requires immediate attention. Inspect Solder Joints: Under high magnification, carefully inspect all sides of the newly soldered PMIC. This detailed inspection not only helps in troubleshooting current problems but also provides valuable insight into the overall internal condition of your device.How to assess smartphone screen yellow tint problems Device Overheating: A failing baseband IC, especially if it's shorted or improperly powered, can cause localized overheating. Do not insert tools too deeply into the device, as this can sever flex cables or damage internal components. Heat gun or heating pad: To soften adhesive holding the screen or back panel. Troubleshooting: The exact current value and duration of the spike are crucial. This problem prevents other apps from using the microphone, leading to failed calls, voice recordings, or voice assistant interactions. Enable USB Debugging: While not always necessary for basic file transfer, enabling USB debugging (Developer options > USB debugging) can sometimes help with recognition, especially for advanced tasks. Device Model and Variant: Accurately identify your phone's exact model number (e.g., SM-G998U for a US Galaxy S21 Ultra, A2484 for an iPhone 13 Pro Max) and its regional/carrier variant. Minimize all ambient noise, as coil whine is often subtle and easily masked. The Display Assembly (Digitizer) is Faulty: This is the most common outcome. If the touchscreen now responds, great! Power off, disconnect the battery, and proceed to full reassembly. Voltage on IC: (Requires schematics and experience) With the phone partially powered (battery connected, but not fully assembled), you could check for voltage on specific test points around the wireless charging IC if a wireless charger is connected. It improves heat transfer and solder flow, making removal easier and safer. Damage: Flex cables are delicate and made of multiple layers of plastic and conductive traces. Inspect under the microscope for cleanliness, flatness, and any lifted pads. Reconnect the new display's flex cables to the motherboard, ensuring they are firmly seated. In Safe Mode, only essential system apps are loaded, disabling all third-party applications. Proper functioning depends not only on the speaker unit itself but also on its electrical connections, especially its grounding. Opening picks (plastic): Thin tools used to separate the case components. Sufficient Battery Life: Ensure your phone is at least 50% charged to prevent unexpected shutdowns during the process, which could cause further issues. If not, power off, disconnect the battery, and recheck all connections. Always remember that prevention is better than cure, so keep your device well-maintained and back up regularly, even if you don't plan a reset.2. Some older or budget models might have a removable plastic back or screw-secured frame. Fix Persistent Software Glitches: For crashes, freezes, non-functional features, or bugs that a simple restart or "Reset All Settings" couldn't resolve. By following this comprehensive guide, you can confidently undertake this repair, bringing your phone's wireless charging capabilities back to full functionality.## 4.

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