How to inspect mobile phones? Mobile phone inspection standards and procedures

How Third-Party Inspection Companies Ensure Mobile Phone Quality: Detailed Explanation of Standards and Processes

In the mobile internet era, mobile phone quality is crucial. Third-party inspection companies use strict inspection standards and processes to ensure that consumers purchase qualified mobile phones.

1. Mobile phone inspection standards

The inspection company conducts a comprehensive inspection of mobile phones based on detailed standards, which are mainly divided into five categories and marked as Critical, Major, or Minor based on the severity of the defects:

1. Assembly inspection:

   • Check each component (front and rear covers, battery cover, flip cover, lens, keyboard, side keys, LCD, battery clip, jack/socket, antenna) for gap uniformity, step difference, fit, alignment, and whether there is any deflection/looseness/warping .

   • Critical: Missing components (such as screws), exposed wires, etc.

   • Major: The lens is tilted, the keyboard is uneven, the LCD is skewed, the jack is blocked, the antenna is tilted, etc.

   • Minor: The gap/step difference slightly exceeds the standard, the side key gap, the screw slippage/flowering/defect, etc.

   • tool: Ruler, feeler gauge, visual inspection, and touch.

2. Appearance inspection:

   • Lens & LCD: Check for stains, bubbles, pits, discolored spots, scratches (fine/hard), rainbow patterns, flow/silver streaks, shrinkage, insufficient filling, fingerprints, poor transparency, light transmittance, poor adhesive backing, and character leveling/centering.

   • Plastic parts (front/back cover, flip cover, SIM card box, antenna, etc.): Check for point defects, scratches, flash, multiple glue points, insufficient filling, silver bars, flow lines, burning, cracks, oil stains, etc.

   • Rubber parts (keyboard, side keys, etc.): Check for discolored spots, multiple glue spots, convex spots, bubbles, stains, and scratches; hard scratches, cracks, printing problems (blurring/broken printing/missing printing/splattering/misalignment/deviation/unevenness), and color difference are not allowed.

   • determination: The judgment is made based on specific standard requirements (such as stain gauge) and sealed samples.

3. Functional test:

   • Covers power on/off, charging, boot screen display, LCD dot matrix (missing lines/dots), ringing (loudness/abnormal sound), vibration, keystrokes, echo, software version, IMEI number, Internet calls, headset function, LCD backlight/brightness, keyboard lock, flip-cover answering, battery safety (bulge/smoke), network/card lock function, alarm, caller ID, SMS, battery calibration, charging time, battery level display, standby time, time settings, ringtone settings, games, phone book, backlight switch , etc.

   • Critical (Cri): Abnormal charging function, LCD dot matrix defects, vibration switch failure, software/IMEI number error, Internet and call failure, headset failure, backlight abnormality, network lock function abnormality, etc.

   • Major (Maj): Boot screen error, ringing issues (loudness/abnormal sound), button failure, echo issues, flip-cover answering/keyboard lock issues, alarm issues, battery parameter/standby time discrepancies, time/ringtone/game/phonebook/backlight setting issues, etc.

   • Minor (Min): Caller ID issues, etc.

   • Note: Items 1-16 are mandatory items for final inspection; items 17-18 are special requirements; items 19-30 are additional/process/inventory inspection items.

4. Index inspection (performance test):

   • Automatic testing (software): RF indicators such as call/talk/hang-up sensitivity, frequency error, phase error, power error, switching spectrum, power time envelope, etc.

   • Sound quality test: Maximum volume output, receiver loudness (RLR), etc.

5. Packaging inspection:

   • Packing List: The format is standardized, the content is accurate, and consistent with the actual object.

   • Logo: The model/quantity/color is correct, the color box label is correct, the three-guarantee logo is compliant, and the qualified logo is clear.

   • Placement: Small packages are placed consistently and packaging areas are isolated.

   • Products and accessories: The packaging is compliant, the instructions are complete and there are no missing pages, the configuration is correct (no missing/extra/extra items), the labels are correct and affixed in accordance with regulations (no skew/warping/defect/inconsistent position).

   • Packing box: The box body is qualified; there are no obvious stains, damages or wrinkles on the box surface, and the color marking is correct.

2. Inspection process of mobile phone inspection by inspection company

Inspection is usually carried out after the product is 100% completed and 80% completed . The inspector performs the following according to the customer's requirements and the above standards:

1. Appearance and process inspection: Check the phone case for obvious appearance defects such as bumps, scratches, and glue overflow.

2. Quantity Conformity Confirmation: Check whether the actual completed quantity and the packaged quantity are consistent with the order/packing list.

3. Product and packaging inspection: Check the phone body, accessories, inner packaging (color box), outer packaging box, box marks, labels, etc.

4. Data measurement and on-site testing (core link, covering functions and some indicators):

   • Adapter high voltage test

   • SIM card/TF card/battery installation check

   • Power on/off interface check

   • Initial setup check

   • Default ringtone and vibration check

   • Hardware/software version check

   • Adapter charging function check

   • Color box/outer box IMEI code consistency check

   • LCD quality inspection

   • Battery function/charge/discharge test

   • Call function check

   • Audio playback function check

   • Camera and video playback function check

   • Headphone function check

   • Bluetooth function check

   • SMS function test

   • Barcode scanning test

   • Friction test (wear resistance)

   • Screen printing test (printing fastness)

   • Inspection of internal processes and key components (disassembly if necessary)

   • Product size measurement

   • Outer box dimensions and weight measurements

   • Outer box drop test (to assess transportation safety)

Inspection completed:

• Communicate inspection results and problems found with the factory on site.

• Prepare a detailed inspection report based on on-site findings and photos taken.

• Reports are typically delivered to clients within one business day .