[SOLVED] I'm looking for KENNED E98 repair guide or schematics (free) - Phones & Tablets Forum

Hi,

I'm hoping you can help me out with my KENNED E98. 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.

@Mario

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 KENNED E98 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/495124/1999+toyota+camry+speedometer+and+mileage+not+working
Take a look at comment #317
Also, this : https://xdaforums.com/t/req-need-good-lockscreen-cm7-2-nighly.1826945/.
You can also check this video starting from minute 10:

The KENNED E98 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 KENNED E98 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 KENNED E98 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 KENNED E98 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://xdaforums.com/t/my-phone-keeps-getting-really-hot.2638644/

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

Troubleshooting a smartphone SIM detection failure systematically can often lead to a successful resolution. OEM (Original Equipment Manufacturer) / Genuine: These are parts made by or for the device manufacturer (e.g., Apple, Samsung). Advanced diagnostics (e.g., using specialized repair tools, analyzing boot logs via UART) might indicate a memory controller communication failure or specific memory initialization errors. For opening the device, a range of precision screwdrivers (Phillips, Pentalobe, Tri-point), plastic spudgers, pry tools, and a suction cup are indispensable. Carefully follow the disassembly guide for your phone model to re-open the device and gain access to the proximity sensor module and the back of the screen. Touchscreen Responsiveness: The entire screen responds accurately to touch. Inspection: Under the microscope, meticulously inspect all solder joints for good contact, no bridges, and proper alignment. Ensure the lens is perfectly clean, free of dust, scratches, or fingerprints. Reseat: Carefully disconnect and then firmly reconnect the display flex cable. Correct Thermal Paste: Use only non-electrically conductive thermal paste. Power On and Test: Before fully sealing the phone, temporarily power on the device to test all functions: touch screen, display, cameras, speakers, microphone, buttons, and charging. After Major Changes: Evaluate boot times after installing a large number of apps, significant data transfer, or a factory reset. Rapid Discharge: If the phone charges to 100% but then dies quickly, even when lightly used, the battery's capacity is likely degraded. This process is highly dependent on the device's manufacturer and chipset. The mid-frame of a smartphone, often overlooked, is a crucial structural component that acts as the backbone of the device. Replace Faulty Battery: If the battery's internal BMS is triggering protection, replace the battery. Warranty Claim: If your phone is still under warranty, contact the manufacturer. Slowly and steadily saw the wire back and forth, moving it across the entire display. Troubleshooting Power Consumption (Battery Drain) Issues on a Smartphone Double-check that the new plastic cover isn't interfering with any internal antenna connections (unlikely if it's the correct OEM part). Thermistors: Often, thermistors are tiny SMD components and can be difficult to replace individually without advanced micro-soldering skills and the correct replacement part. Liquid Damage Indicators: Look for any signs of liquid ingress around the button or charging port. Prepare the new fuse: Place a tiny amount of solder on each of the cleaned pads on the motherboard (pre-tinning). Screen Protectors: A common culprit for proximity and ambient light sensor issues. Small screwdrivers (Phillips, Pentalobe, Tri-wing , depending on your phone model) If a via connects to internal layers and there are no accessible traces or components on the surface layers that directly correspond to its pathway, repair can become impossible without specialized, invasive techniques. Disconnect Battery: Once the phone is open and you have access to the internal components, the very first step is to disconnect the battery flex cable. System UI Crashes: The user interface freezes, becomes unresponsive, or displays "System UI isn't responding" messages. The flux will activate, and the solder will melt, causing the component to "self-align" slightly due to surface tension. To enable Developer Options, go to `Settings > About Phone`, then tap "Build Number" seven times until a message confirms developer options are enabled.

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