If flashing fails repeatedly β NAND issue confirmed.
Step 2: Chip Removal (if required)
Use hot air station to carefully remove NAND chip from motherboard.
Protect nearby components with Kapton tape.
Step 3: Chip Connection
Place NAND chip in programmer socket or connect via test points.
Some tools support ISP (In-System Programming) β no need to remove chip.
Step 4: Read & Backup
Use programmer software to read dump of old NAND.
Always keep backup of IMEI / security partitions.
Step 5: Erase & Reprogram
Erase bad data from NAND.
Write fresh firmware + security data.
Repair IMEI if required.
Step 6: Verification
After programming, verify written data.
Re-solder NAND back to motherboard (if removed).
Step 7: Testing
Power on mobile.
Check if device boots properly and storage is detected.
β‘ Pro Tips for Technicians
Always keep a full dump library for different models.
Avoid overheating NAND during removal β it can get permanently damaged.
Use good quality flux for reballing/soldering.
ISP method is safer for beginners (no risk of chip damage).
NAND reprogramming is mostly required in Samsung, Oppo, Vivo, Xiaomi phones.
β Benefits of NAND Programming
Revives dead phones
Fixes boot loop and storage errors
Saves customerβs data (if backup is possible)
Adds advanced-level income for technicians
Meta Description
NAND Chip Programming in Mobile Repair explained β Learn a step-by-step guide for diagnosing, removing, reprogramming, and repairing NAND flash in dead or boot loop phones.
Finger test / thermal camera use karke heating component identify karo
Step 5: Heat Method π‘οΈ
Agar faulty capacitor/IC short hai β woh jaldi garam hoga
Heat spot par component replace karo
Step 6: Isolation Method βοΈ
Shorted section trace karke components remove karo one by one
Short disappear hone par faulty part confirm ho jata hai
Step 7: Repair / Replace π§
Faulty capacitor/IC ko replace karo
Jumper ya reballing sirf tab karo jab zaroori ho
Pro Tips for Technicians
Hamesha low voltage se start karo jab DC Power Supply use kar rahe ho
Kapton tape use karke nearby components protect karo jab heat do
Agar short capacitor mil jaye β usko nikal kar phir line check karo
Always cross-check with schematic diagrams (ZXW, Wuxinji)
β Benefits of Correct Short Circuit Tracing
Time save hota hai
Repair success rate improve hoti hai
Customer ko long-lasting solution milta hai
Shop ki reputation grow hoti hai
Meta Description
How to Trace Short Circuit in Mobile Motherboard β Complete step-by-step guide using multimeter, DC power supply, and heat detection methods for mobile repair technicians.
Tags
short circuit in mobile, mobile motherboard repair, short tracing guide, dc power supply mobile repair, multimeter short test, capacitor short in phone, mobile repair step by step, dead phone repair
50x+ β For deep inspection (cracks in IC pins, reballing inspection)
π Rule: Use the lowest magnification that gives a clear view β it reduces eye strain.
π§ 2. Focus Adjustment
Always adjust focus so that the component appears sharp and crystal clear.
Keep your working distance (between microscope lens & motherboard) comfortable β around 10cm is ideal for soldering.
π§ 3. Lighting Settings
LED Ring Light is best β Provides even light without shadows.
Adjust brightness according to surface reflection.
For shiny ICs or solder balls β Use slightly angled lighting to avoid glare.
π§ 4. Camera/Display Settings (if using Digital Microscope)
Resolution: 1080p minimum for clear recording.
Frame rate: 30β60 FPS for smooth video.
Brightness/Contrast: Adjust to highlight tiny solder joints.
β‘ Pro Tips for Using Microscope in Mobile Repair
Keep your eyes 2β3 cm away from eyepiece to reduce strain.
Always secure motherboard on a PCB holder for stable view.
Use anti-glare lens covers if you work long hours.
If doing reballing β magnification around 35x is most comfortable.
Clean the microscope lenses regularly with microfiber cloth.
β Benefits of Correct Microscope Settings
Precision in micro soldering
Faster repair time
Reduced mistakes on fine components
Less eye fatigue for technicians
Professional results for customers
π Meta Description (SEO)
Best Microscope Settings for Mobile Repair Technicians explained. Learn ideal magnification, focus, lighting, and pro tips to make micro soldering and board repairs easier.
π Tags (Ready-to-Paste)
best microscope settings, microscope for mobile repair, mobile repairing microscope guide, microscope magnification soldering, mobile repair tools, trinocular microscope setup, digital microscope mobile repair, soldering under microscope
π Jani, yeh guide technicians aur students dono ke liye bohot kaam ki hai.
Kya chahte ho mai agli baar likhun βHow to Use DC Power Supply in Mobile Repairing β Complete Guideβ?
You said:
Ab is pr likhy
Importance of Oscilloscope in Mobile Repair
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Shandar topic jani π₯
Oscilloscope ka use har advanced mobile repair technician ko ana chahiye, warna motherboard level kaafi issues samajhna mushkil hojata hai. Chalo detail aur professional guide likhte hain:
Importance of Oscilloscope in Mobile Repair β‘π±
π Oscilloscope Kya Hota Hai?
Oscilloscope ek advanced testing instrument hai jo voltage signals ko waveform (graph form) me dikhata hai. Simple multimeter sirf voltage, resistance ya continuity batata hai, lekin oscilloscope signal ka behavior live show karta hai β jaise frequency, amplitude, aur noise.
Mobile repairing me, ye tool hidden problems detect karne ke liye best hai jo normal tools se identify nahi hoti.
π Why Oscilloscope is Important in Mobile Repair?
Diagnosing Dead Mobiles
Boot sequence signals check karne ke liye.
CPU aur eMMC ke communication signals dekhne ke liye.
Agar line noisy ho to mobile boot issue create hota hai.
Audio & Network Troubleshooting
Audio IC me signals verify karna.
RF/Network circuits me waveform dekhna.
Short Circuit Analysis
PCB par unusual waveforms trace karke faulty component identify karna.
βοΈ Basic Oscilloscope Settings for Mobile Repair
Time/Div (Horizontal Scale): Adjust to capture signal speed (e.g., fast clock signals need smaller scale).
Volt/Div (Vertical Scale): Adjust according to signal level (1V, 3.3V etc.).
Trigger Setting: Stable waveform ke liye proper trigger set karna.
Probe Setting: Use x10 probe for motherboard testing (better accuracy).
π§ Practical Uses for Technicians
CPU & eMMC Communication Check
Dead mobile repair me sabse zyada use hota hai.
Agar data lines me waveform nahi β CPU/eMMC issue.
Backlight & Display Lines
LCD/LED signals verify karna.
No display issue easily identify hota hai.
Battery Charging Circuit
Charging IC ke switching waveform observe karna.
Touch & Sensor Issues
Capacitive touch signals check karna.
β‘ Pro Tips
Hamesha ground probe motherboard ke ground par connect karo.
Start with low voltage scale (1V/div) aur gradually increase karo.
Short detection me oscilloscope ko DC Power Supply ke sath use karna bohot effective hai.
Agar beginner ho, to 2-channel oscilloscope enough hai.
Advanced repair shops ke liye 4-channel digital storage oscilloscope (DSO) recommended hai.
β Benefits of Using Oscilloscope
Hidden faults easily detect hote hain.
Saves time in dead mobile & IC level repairs.
Increases repair accuracy & success rate.
Professional service quality improve hoti hai.
Customer trust barhta hai jab aap advanced tools use karte ho.
Meta Description
Mobile Power Key / Volume Key Repair Guide. Learn easy step-by-step process to clean, test, replace, or jumper faulty keys in mobile phones.
Tags
mobile power key repair, volume button not working, mobile key jumper, power key solution, volume key problem, power button replacement, mobile repairing guide, mobile hardware repair
Power key aur volume buttons mobile ke sabse zyada use hone wale parts hain. Rozana bar-bar press karne se ye kharab ho jate hain. Common issues:
Button press hota hai lekin kaam nahi karta
Button press hi nahi hota (stuck ya broken)
Phone on/off nahi hota due to faulty power key
Volume up/down automatic press hota rehta hai
Water damage se carbon / rust lag jata hai
Tools Required
Precision screwdriver set
Tweezer & pry tools
Multimeter
Soldering iron / hot air gun
Isopropyl alcohol + brush
Replacement key (power/volume flex)
Step-by-Step Repair Process
Step 1: Initial Check
Confirm whether itβs button problem ya software hang.
Restart phone using charging cable or test with ADB commands (if possible).
Step 2: Physical Inspection
Check button movement β Free hai ya jammed.
Open mobile carefully & locate power/volume key flex.
Step 3: Cleaning
If button contacts have dust or rust β Clean with isopropyl alcohol.
Sometimes sirf cleaning se hi issue solve ho jata hai.
Step 4: Continuity Test (Multimeter)
Place probes on key points.
Jab button press ho to multimeter beep kare β key working.
Agar beep nahi β button faulty.
Step 5: Replacement
If key/flex is broken β Replace new original part.
Desolder old key carefully with hot air.
Solder new button neatly without damaging PCB lines.
Step 6: Jumper Solution (if required)
Agar flex connector pad damage ho gaya hai β Jumper wire use karo.
Jumper diagram follow karna zaroori hai.
Step 7: Testing
Reassemble mobile β Test all buttons (power, volume up, down).
Make sure phone boots and responds properly.
β‘ Pro Tips for Technicians
Always use original key flex for long life.
Donβt overheat during desoldering β nearby IC damage ho sakta hai.
Power key ke bagair mobile DC Power Supply se jump start karke bhi check kar sakte ho.
Customer ko hamesha batayein ke duplicate keys zyada time nahi chalti.
β Benefits of Correct Repair
Customer ka phone normal tarike se use hone lagta hai.
Frequent issues (auto restart, no boot) solve ho jate hain.
Shop ki reputation barhti hai jab aap clean aur durable repair dete ho.
Meta Description
Mobile Power Key / Volume Key Repair Guide. Learn easy step-by-step process to clean, test, replace, or jumper faulty keys in mobile phones.
Tags
mobile power key repair, volume button not working, mobile key jumper, power key solution, volume key problem, power button replacement, mobile repairing guide, mobile hardware repair
Ghost Touch Problem in Mobiles – Causes and Repair
Ever noticed your mobile screen opening apps, typing messages, or scrolling on its own β without you touching it? Thatβs called the Ghost Touch problem. Itβs one of the most frustrating issues for users and a common case in mobile repairing shops. This guide explains what ghost touch is, its causes, and step-by-step solutions for both users and technicians.
π What is ghost touch?
Ghost touch (also called phantom touch) happens when your screen responds to touches you didnβt make. For example:
Random typing
Apps opening automatically
Screen scrolling without your input
Difficulty controlling the phone
This is usually a hardware-related issue, but sometimes software can also play a role.
β οΈ Common Causes of Ghost Touch
Faulty Touch Screen / Digitizer
A damaged or low-quality digitizer can cause random signals.
Loose or Damaged Display Connector (Flex)
If the display flex cable isnβt properly seated or has carbon/dust, it can trigger ghost touches.
Moisture or Dust Inside Screen
Even small drops of water or sweat trapped between glass and touch can cause misbehavior.
Screen Protector Issues
Cheap or poorly applied tempered glass can interfere with touch sensitivity.
Electrostatic Discharge (Static Electricity)
Static build-up in low-quality chargers or cables.
Motherboard Issues (Touch IC)
Damaged IC or shorted circuit on the board.
Software Glitches
Rare, but corrupted firmware or buggy OS updates can cause ghost touch.
π Quick Fixes for Users
Before rushing to the repair shop, try these steps:
Clean the Screen π§½
Wipe the screen with a soft, dry cloth. Remove dirt, oil, or moisture.
Remove Screen Protector / Tempered Glass βοΈ
Sometimes ghost touch disappears after removing a poor-quality screen protector.
Restart or Update Software π
Restart the phone and check for pending updates.
Use Original Charger & Cable β‘
Low-quality chargers often create static electricity, leading to ghost touches.
Check Safe Mode (Android)
Boot into Safe Mode. If ghost touch disappears, it could be caused by a faulty app.
π§ Repair Guide for Technicians
If the above steps donβt solve it, hereβs how professionals should proceed:
1. Check Display Flex & Connector
Open the device carefully.
Clean the display connector with isopropyl alcohol.
Reseat or replace the flex if damaged.
2. Replace Touch Screen/Digitizer
If ghost touch persists, replace the faulty digitiser.
Always use original or high-quality parts to avoid comebacks.
3. Check Motherboard (Touch IC Issue)
Inspect the touch IC under a microscope.
If shorted or damaged, replace the IC with proper soldering tools.
4. Dry Out Moisture
If moisture is present, clean with alcohol and use a heat gun/blower for proper drying.
5. Re-flash / Update Software
As a last step, re-install the official firmware. This eliminates any software corruption.
Prevention Tips for Customers
Always use quality screen protectors and covers.
Avoid using phones with wet or sweaty hands.
Use original chargers & cables.
Never drop the phone β most ghost touch cases are due to screen/connector impact.
Meta Description
Ghost Touch Problem in Mobiles β Causes and Repair explained. Learn why your phone screen touches itself and how to fix ghost touch with easy steps for users and technicians.
Tags
ghost touch problem, phone touches itself, ghost touch repair, mobile touch problem solution, causes of ghost touch, phantom touch fix, touchscreen repair guide, ghost touch in android,
Mobile viruses and malware are real β they steal data, drain batteries, show unwanted ads, mine crypto, or even brick phones. The good news: with the right habits, tools, and a step-by-step plan, you can protect your phone and remove infections quickly. This guide shows practical, shop-tested steps for both everyday users and technicians. Letβs keep your mobile safe. β
βMobile virusβ is a general term that includes:
π Quick Overview β What βMobile Virusβ Means
Malware (spyware, trojans, adware)
Ransomware (locks files/phone until paid)
Potentially Unwanted Programs (PUPs)
Malicious apps that abuse permissions
Symptoms: sudden battery drain, overheating, lots of pop-up ads, high data usage, unknown apps installed, weird notifications, slow performance, unknown charges, or apps asking for admin privileges.
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π Immediate Actions If You Suspect Infection
1. Airplane Mode / Disconnect βοΈ
Put the phone in Airplane Mode (or turn off Wi-Fi & mobile data). This stops data exfiltration and remote commands.
2. Do NOT enter passwords / OTPs π
Avoid logging into banking or sensitive accounts until your device is clean.
3. Reboot into Safe Mode (Android) π§°
Safe Mode disables third-party apps so you can check if a downloaded app is the culprit. (iPhone equivalent: uninstall suspicious apps; iOS malware is rare but possible on jailbroken devices.)
4. Take a backup (if possible & safe) πΎ
If you can still access important files, back them up to a trusted computer or cloud account β but donβt back up apps or executables that may reintroduce malware.
π Step-by-Step Removal (User Level)
1. Uninstall suspicious apps
Settings β Apps β look for recent installs or apps you didnβt authorize β Uninstall.
For apps with device admin permission, first revoke admin: Settings β Security β Device Administrators.
2. Clear browser data
Pop-up ads often come from malicious web redirects. Clear browsing history, cookies, and site data.
3. Install trusted mobile antivirus π§°
Use a reputable scanner (look for established vendors). Run a full scan and follow removal prompts. (For Android use Google Play only; for iPhone, anti-malware options are limitedβrely on iOS security and remove suspicious profiles or MDMs.)
4. Update OS & apps π
Patches often close vulnerabilities malware exploits. Update system and installed apps from official stores.
5. Factory Reset (last resort) π
If infection persists, backup data (photos, contacts) and factory reset. This usually removes all malware β but ensure backups donβt reintroduce the threat.
[ ] Backup clean data, then factory reset if needed
[ ] Reflash firmware if infection persists (technician)
π Meta Description
How to save your mobile from viruses: practical steps to detect, remove and prevent malware on phones. Immediate actions, removal steps, technician tips, and long-term protection.
mobile virus removal, how to remove malware from phone, protect phone from viruses, android virus removal guide, mobile malware removal steps, prevent mobile virus, phone security tips, remove adware on phone, fix infected smartphone
A βdeadβ phone is one of the scariest customer cases β no lights, no vibration, nothing. But donβt panic: many βdeadβ phones are recoverable with a systematic approach. Below is a practical, shop-tested, step-by-step workflow you can follow to diagnose and repair dead mobiles like a pro. Iβll cover tools, safety, basic checks, board-level diagnostics, common failure points, and final testing. Letβs get it alive again. π
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1) Safety First β
Remove the battery (if removable) before doing board-level work.
Use ESD protection: wrist strap + ESD mat. β‘
Work in a well-ventilated spot; use fume extraction when soldering.
If battery is swollen, do not attempt recharging β replace it safely.
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2) Tools Youβll Need π§°
Digital multimeter (continuity/diode/resistance)
Bench DC power supply (adjustable voltage + current limit)
Hot-air rework station & soldering iron (temperature-controlled)
Microscope or good magnifier
Tweezers, solder wick, flux, solder paste
Thermal camera or freeze spray (optional but very helpful)
Isopropyl alcohol (IPA) and soft brushes
Screwdrivers, plastic spudgers, SIM tool
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3) Begin with the Basics (Customer & External Checks) π
1. Ask customer questions: model, last known condition, water exposure, lightning or drop event, any recent repairs or software updates.
2. Try different chargers and cables (use a known-good original adapter).
3. Test with a different, known-good battery (if removable) or try the phone with DC power supply at battery pads (set current limit low).
4. Inspect the charging port and battery connector for corrosion, debris, or bent pins.
—
4) Power-Up Attempts & DC Supply Method β‘
Set DC supply to battery voltage (3.7β4.2V) and a safe current limit (start 0.5A β 1A).
Connect to battery pads; watch the current:
Very high current (>1A) immediately β short somewhere on board.
No draw β open circuit (bad fuse, connector, broken track, or main IC fault).
Use current reading to triage: high draw β hunt for short; no draw β hunt for open/fuse.
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5) Visual & Microscopic Inspection π
Look for burnt components, blown capacitors, damaged coils, lifted pads, or corrosion.
Check battery connector pads, charging port area, and power management IC vicinity.
Smell can help β burnt smell often points to a shorted IC or burnt track.
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6) Continuity & Voltage Checks with Multimeter π§ͺ
Check fuses, bead inductors, and large caps on VBAT line for continuity.
Measure voltage at battery pads when DC supply is connected.
Trace VBAT to PMIC (power management IC), charging IC, and main power rails. No voltage where there should be voltage indicates a broken path or bad component.
If hardware passes and phone shows signs of life (LEDs, vibration), try booting into recovery or fastboot.
Reflash stock firmware if bootloader responds β sometimes a corrupt firmware prevents boot.
If device is locked and wonβt boot after hardware fixes, proceed to data recovery precautions before flashing.
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10) CPU/eMMC Level Faults (Advanced) π¬
If the phone shows signs of life but wonβt boot (stuck on logo), suspect eMMC, boot partitions, or CPU solder joints.
Options: reball CPU, reball eMMC, or perform chip-off data recovery with professional programmers (UFI, Medusa, JTAG) β advanced tools required.
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11) After Repair β Testing & Quality Control β
Power up with DC supply first; ensure current draw is normal.
Test charging, boot, screen, touchscreen, Wi-Fi, audio, cameras, sensors.
Run a stress test 10β30 minutes (burn-in) to ensure stability.
Reassemble and test again. Provide short warranty for the repair.
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12) Customer Communication & Data Safety π£οΈ
Explain what you tested and what was replaced.
If you needed to erase/flash, obtain written consent and backup if possible.
Be transparent about parts used (original vs. compatible) and warranty.
—
Pro Tips from the Bench π―
Always start simple: chargers, cables, batteries β most βdeadβ calls are accessory related.
Keep a logbook: model, symptom, tests, voltages, fix β great for future reference.
Use current-limited DC supply to avoid frying the board while testing.
Practice BGA rework and reballing on scrap boards before touching customersβ devices.
If uncertain, isolate and replace inexpensive parts first (fuses, caps) before high-cost ICs.
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Checklist (Printable)
[ ] Remove battery & ESD protection on
[ ] Test with known-good charger & cable
[ ] DC supply connection + observe current
[ ] Visual inspection under microscope
[ ] Continuity & voltage checks on Vbat rails
[ ] Localize short (thermal/freeze) or open (fuse/tracks)
[ ] Replace/repair components; retest power
[ ] Boot & software checks; reflash if needed
[ ] Full functional test & burn-in
[ ] Customer briefing & warranty
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Meta Description (SEO)
Dead mobile repair step-by-step guide: diagnose no-power phones with DC supply, multimeter, short detection, PMIC/charging fixes, and advanced CPU/eMMC tips for technicians.
