L4 Technician – Mobile Repairing Steps (Android & Apple)

1. Job Card Verification

 Review customer complaint carefully.

 Check device history (previous repairs, water damage, physical damage).

 Confirm warranty / out-of-warranty status.

 Note visible defects before opening the device.

2. Initial Diagnosis - Perform basic functional check:

o Power ON/OFF / Display / Charging / Network / Camera / Touch

 Identify whether the issue is software or hardware.

Golden Rule: Never open the phone before basic testing unless it is completely dead.

3. Visual Inspection

o Check for -Liquid damage indicators / Burn marks / Corrosion / Broken

connectors / Loose components

Use a microscope for motherboard inspection when required.

4. Power Testing (For Dead Phones) - Connect to DC Power Supply.

Possible Observations:

 No current draw: Battery / charging IC / power IC issue.

 High current / short: Locate shorted capacitor or IC.

 Boot current but no display: Check display line or backlight circuit.

5. Disassembly with ESD Protection

 Wear an ESD wrist strap / Use an anti-static mat. / Remove components

systematically to avoid flex damage.

⚠Especially important for iPhones (Face ID, Touch ID, True Tone components).

6. Advanced Motherboard Diagnosis

Follow a structured approach:

✔ Check Power Rails - Measure voltages using schematics (if available).

✔ Identify Short Circuits - Use multimeter / thermal camera / freeze spray.

✔ Inspect Common Failure Areas - Power IC / Charging IC / Baseband section / Audio IC /

Backlight circuit

7. Micro-Soldering / Board-Level Repair

Perform only after confirming the fault.

Steps:

1. Shield nearby components with heat-resistant tape.

2. Apply flux.

3.



Use controlled temperature (typically 320–380°C).

4. Remove faulty component.

5. Clean pads.

6. Reball or replace IC.

7. Inspect solder joints under microscope.

8. Apple-Specific Precautions

 Preserve original paired parts (Face ID, Touch ID).

 Avoid flex damage.

 Maintain battery health data where applicable.

 Restore True Tone after display replacement.

 Use programmer tools when required.

9. Android-Specific Steps

 Flash firmware if software-related.

 Repair IMEI/baseband issues carefully.

 Calibrate fingerprint sensors after replacement.

 Verify quick charging protocols.

10. Cleaning & Reassembly

 Clean board with Isopropyl Alcohol (IPA) after soldering.

 Replace thermal pads if removed.

 Ensure proper screw placement.

 Reassemble dust-free.

11. Quality Testing (Mandatory)

Never skip QC.

✔ Network signal / Wi-Fi & Bluetooth / Camera / Sensors / Audio / Charging / Battery drain

/ Heating test

Run the device for 15–30 minutes when possible.

12. Final Quality Check

Ask yourself:

Is the original complaint resolved?

Did I create any new issue?

Is the device cosmetically safe?

Use a QC checklist for consistency.

L4 Technician Best Practices

 Avoid trial-and-error repairs.

 Always diagnose before replacing parts.

 Focus on first-time-right repair.

 Support junior technicians when needed.

 Balance repair cost vs device value.

Pay: ₹20,000.00 - ₹60,000.00 per month

Benefits:

- Health insurance
- Leave encashment
- Paid sick time
- Paid time off
- Provident Fund

Application Question(s):

- What is your current take home salary?
- What is your Notice period?
- Which location you are from?

Work Location: In person

📌 Mobile Technician (India)
🏢 Congruence Holdings
📍 India