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

Hi,

I'm hoping you can help me out with my Asus ZenFone 5Q. 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.

@Pascal

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 Asus ZenFone 5Q 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/acer-iconia-one-7-b1-740.2808796/
Take a look at comment #623
Also, this : https://xdaforums.com/t/playstore-sort-option-by-updated-date-etc-mod.3227360/.
You can also check this video starting from minute 7:

The Asus ZenFone 5Q 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 Asus ZenFone 5Q 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 Asus ZenFone 5Q 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 Asus ZenFone 5Q 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/bootanimations-flash-twrp-zip.3848845/

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

This is usually due to the battery not being reconnected, or the display/digitizer flex cables being damaged or improperly seated. Enhanced Immersion: Especially for gaming and video playback, stereo sound provides a more immersive experience. Battery Drain: Corrupted files can cause processes to run in an endless loop or consume excessive resources, leading to rapid battery depletion. Check for Software Updates: Outdated software can sometimes cause charging anomalies. This is particularly noticeable in a dark room with the screen turned on, especially displaying a white background. If present, disconnect them carefully with a plastic spudger after lifting the cover slightly. Some third-party tools (e.g., JCID, QianLi) claim to be able to "read and write" data from original Face ID components to new ones, but this is a complex and often unreliable process, limited by iOS software updates. While generally beneficial, some users prefer to turn it off for a consistent white point. Boot into Safe Mode (Android Only): If the lines appeared in the screenshot, try booting into Safe Mode. Using ESD-safe tweezers or a plastic spudger, gently peel or lift off the old thermal pads. Another diagnostic step involves resetting your smartphone's network settings. Adhesive Residue: Removing the old gasket often leaves behind stubborn adhesive residue on both the frame and the screen/back cover. Camera Application Usage: The camera module and its associated image signal processor (ISP) can draw significant power, particularly during video recording, using advanced camera features (like optical image stabilization, specific filters), or while the flash is charging. Educate the Customer: If the volume isn't an exact match but is within acceptable parameters, inform the customer that aftermarket parts can have slight variations. Then, carefully re-solder or re-attach the component, ensuring the jumper wire provides the connection. A yellow tint on a smartphone screen can be a perplexing issue for users, ranging from a subtle warmth to an overtly jaundiced display. Start with simple software resets, then proceed to hardware inspection of the display flex cable and its connector. These layers are connected by tiny vertical holes called vias, which are crucial for electrical continuity. Overcharge Protection: Prevents the battery from being charged beyond its safe voltage limit, which can cause swelling or even thermal runaway. The ambient light sensor is almost always integrated into the front flex cable assembly, typically located at the top of the display. Limitations: Rarely works on modern, encrypted devices (Android 6.0+). Battery usage graphs might show the phone's "awake" bar almost constantly active, indicating something is preventing it from truly resting. Coil Damage: Inspect the charging coil itself for any visible damage, kinks, tears, or discoloration from heat. A cable might be frayed, have bent internal pins, or use substandard wiring preventing proper data or power transmission. Cable Routing: Double-check that all flex cables are correctly seated and routed, ensuring no crimping or pinching. Disassemble Quickly: The faster you can get inside the phone, the better. It's often accelerated by the presence of electrolytes (from water, especially salt water or sugary drinks) and electricity (if the phone was powered on). Main Microphone: Usually located at the bottom of the phone, near the charging port, for voice calls. However, for those who crave ultimate control and are willing to navigate the complexities, rooting remains a powerful pathway to unlock their device's true potential.5. Check for OS Updates: Ensure your phone's operating system is up to date.

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