[SOLVED] I'm looking for Coolpad Cool 5 repair guide or schematics (free) - Phones & Tablets Forum

Hi,

I'm hoping you can help me out with my Coolpad Cool 5. 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.

@Paco

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 Coolpad Cool 5 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/a-complete-htc-hd-2.1248612/
Take a look at comment #1124
Also, this : https://xdaforums.com/t/mhl-hdmi-adaptor-on-metropcs.2533087/.
You can also check this video starting from minute 10:

The Coolpad Cool 5 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 Coolpad Cool 5 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 Coolpad Cool 5 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 Coolpad Cool 5 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/451155/Put+in+2000mAH+big+battery+in+iPod+3gb

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

Inspect and Clean: Under the microscope, meticulously inspect every pad for cleanliness, flatness, and any signs of damage (lifted, missing, or corroded pads). Heat gun or hot plate (for devices with strong adhesive, especially screens) Distance: Test focusing on very close objects (macro), mid-range subjects, and distant landscapes. Universal Tools: For devices that use Fastboot (like Google Pixel, OnePlus), you'll need the Android SDK Platform-Tools (which include ADB and Fastboot binaries). Once all pins are visibly soldered, gently tap the component with tweezers to ensure it's firmly seated. Once a small gap is created, immediately insert a plastic opening pick or guitar pick into the gap. Final Checks: Once the phone is fully reassembled, perform a final, comprehensive test of all functions to ensure everything is working as expected. The first step in diagnosing an earpiece mesh obstruction is a simple visual inspection. Observe any nearby tiny components (resistors, capacitors, ICs) that might be susceptible to heat or displacement. If comfortable, you can use a multimeter to test for continuity on the flex cable or voltage readings at different points on the logic board to confirm power flow. Battery Disconnection: Once the display or back panel is partially opened, locate the battery connector. You can click on a component and see its name, function, and related traces. Physical Damage: Inspect the exterior of the phone for any obvious signs of damage, such as dents or cracks, particularly around the corners or edges where antennas might be located. If a short is found in Step 2, this method helps locate the culprit component. You'll need to apply heat for longer and might need to gently pry from one side with a thin, plastic blade as you heat. Apply heat with the hot air station evenly over the chip, following a controlled thermal profile. Always photograph the original connections before disconnecting anything, and double-check wiring diagrams or repair manuals specific to your phone model to ensure correct reassembly. Most devices allow you to re-lock the bootloader using a command like `fastboot flashing lock` or `fastboot oem lock`. Always prioritize safety, especially when dealing with swollen or damaged batteries, and seek professional assistance if you are uncomfortable with any repair step. If software troubleshooting doesn't yield results, the problem is almost certainly hardware-related. The official stock firmware package for your exact phone model and region. Stuttering in games often indicates the phone is struggling to render frames quickly enough. Labeled Bins/Containers: Use clear, labeled bins or small plastic containers to store components (e.g., "iPhone 11 Screens," "Samsung S20 Cameras," "Assorted Flex Cables"). They offer a strong balance of performance, durability, and cost-effectiveness. Excessive Heat Generation during Boot: The device becomes noticeably warm while struggling to boot. Use a soldering iron with a fine tip and solder wick to carefully remove excess solder from each pad. Short Circuits: A short on the motherboard (e.g., a shorted capacitor, a damaged power management IC (PMIC), or a faulty Wi-Fi/Bluetooth chip constantly drawing power) can cause significant, rapid battery drain even when the phone is idle or off. Intermittent Issues: Could be a partial reflow or subtle damage elsewhere. It’s a vital skill for maintaining the longevity and performance of modern smartphones, ensuring all components operate efficiently without succumbing to heat-related stress.### 2. Water Damage: Corrosion on the flex cables or within the components can cause shorts or open circuits.

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