[SOLVED] I'm looking for VELOCITY A68 repair guide or schematics (free) - Phones & Tablets Forum

Hi,

I'm hoping you can help me out with my VELOCITY A68. 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.

@Arlene

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 VELOCITY A68 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/741934/Monitor+has+vertical+lines+at+start-up.
Take a look at comment #616
Also, this : https://www.ifixit.com/Answers/View/267560/Why+are+my+speakers+not+working.
You can also check this video starting from minute 1:

The VELOCITY A68 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 VELOCITY A68 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 VELOCITY A68 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 VELOCITY A68 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/843549/old+kenmore+washer+&+matching+dryer

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

The phone might start off performing well, but after a few minutes of sustained load, performance noticeably degrades. Also, inspect any rubber inserts that might be part of the bracket assembly. They are located on the battery and/or logic board and monitor the device's temperature to prevent overheating during charging. If you're using a replacement component that already has solder balls (BGA package), ensure they are perfectly aligned with the pads on the motherboard. Adaptive Refresh Rates (LTPO/Variable Refresh Rate): Many flagship phones now incorporate adaptive refresh rate technology (often using LTPO, Low-Temperature Polycrystalline Oxide, display panels). OEM Unlocking (if necessary): For some devices, especially if you were previously rooted or using a custom ROM, you might need to enable "OEM Unlocking" in Developer Options. This guide will walk you through the process of replacing a wireless charging coil/module in a smartphone. If you jumper the fuse without fixing the underlying problem, you're almost guaranteed to cause more damage. What to Look For: 90% concentration or higher is ideal (99.9% is best for electronics). Connect the Flex Cable: Align the flex cable from the new camera module with its connector on the motherboard. Ensure you have good cellular reception whenever possible, as a struggling modem is a major power drain. Troubleshooting Smartphone Issues Related to External Accessory Connection (Dongles) Inner Folding Screen Replacement: This is the most frequent and expensive repair. - You observe exceptionally weak signal or inability to detect networks, even when very close to a router. Cut small, thin pieces of high-density foam, soft rubber, or specialized adhesive foam (like 3M VHB tape) to the required size and shape. Incomplete Removal of Old Adhesive: Leaving remnants of the old adhesive creates an uneven surface and reduces the contact area for new adhesive. The key to diagnosing a black screen on an otherwise functional phone is confirming the phone is indeed "on." Try calling your number from another phone to see if it rings. Test with Known Good Accessories: Acquire a known-good, original, or high-quality USB cable and wall adapter. Adhesive Seals: Many modern phones use strong adhesives for water resistance. Limitations: May not work if the phone is heavily damaged or won't boot at all. Hard Brick: The phone becomes completely unresponsive and unable to boot, even into special modes. Ensure all flex cables are properly seated, screws are tightened (but not overtightened), and any removed shields are replaced. If basic tests are positive, power off the phone, disconnect the battery, and proceed with full reassembly of the smartphone in reverse order. Clear Workspace: Work on a clean, well-lit, and anti-static protected surface. Evaluating and diagnosing such issues requires a methodical approach, distinguishing between software glitches, environmental interference, and underlying hardware faults. If detected, cease use immediately and seek professional repair, as a swollen battery poses a fire risk. Partial Reassembly: Before fully sealing the device, reassemble enough to power it on (logic board, display, battery). A single breach of trust can permanently damage a business's reputation. Does the phone get excessively hot immediately before or during the boot loop? Connector Damage: The tiny pins inside press-fit connectors, or the locking tabs on ZIF connectors, are extremely fragile.

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