Device Troubleshooting & Repair Flashcards

A tablet's USB-C port passes data but won't charge from any charger. The port pins look clean. What internal component is most likely faulty?

Answer: Battery management IC / charge controller IC

The charge controller IC manages power delivery negotiation and charging circuits; a failure here prevents charging while data functions remain intact.

A phone shows ghost touches (screen inputs with no physical contact) after a screen replacement. What is the most likely cause?

Answer: Poor quality or incompatible digitizer, or digitizer flex cable not fully seated

An incompatible or poorly seated digitizer generates false electrical signals interpreted as touch inputs by the controller.

A phone's microphone doesn't work during calls but voice memos record fine. What does this indicate?

Answer: The secondary (top/noise-canceling) microphone used for calls is defective

Modern phones route calls through a specific microphone (often the secondary/top mic for noise cancellation) while voice memos use the primary bottom mic.

After a battery replacement on a device that uses pentalobe screws, the technician realizes they stripped one screw. What is the recommended next step?

Answer: Use a rubber band between screwdriver and screw head for added grip, or use a left-handed screw extractor bit

A rubber band fills stripped screw head grooves to provide enough friction for removal; a screw extractor is the professional alternative for badly stripped screws.

A customer brings a phone with a shattered back glass. The device functions perfectly otherwise. What repair approach preserves most device integrity?

Answer: Back glass replacement using a heat gun to soften adhesive and a thin pry tool

Carefully heating the adhesive and prying the back glass panel allows replacement while preserving the original internal components and motherboard.

A technician notices a swollen battery in a device brought in for an unrelated screen issue. What is the correct professional response?

Answer: Inform the customer immediately, refuse to apply pressure to the device, and recommend immediate battery replacement

A swollen lithium battery is a fire and explosion hazard; the technician must prioritize safety by stopping work and informing the customer immediately.

What is the purpose of using UV-curable adhesive (LOCA) when bonding a replacement display assembly?

Answer: It fills air gaps between the glass and display panel to improve optical clarity and bond strength

LOCA eliminates the air gap that reduces brightness and causes glare, bonding glass to panel for improved display quality and structural integrity.