220-1101 Mobile Devices Practice Test 10 — 15 Questions

Question 1

A user reports that their iPhone is not recognized by a Windows computer when connected via USB. The user has tried three different USB cables, all of which allow the phone to charge normally. The user also tested another iPhone with the same computer and it was recognized. The iPhone's 'Trust This Computer' prompt appeared and was accepted. Which of the following is the MOST likely cause of the issue?

Choose an answer to begin — your selection is scored in the full session.

Accepted Answer

The Lightning port on the iPhone has damaged data pins.. The fact that the iPhone charges normally but is not recognized by the computer indicates that the power pins in the Lightning connector are functioning, but the data pins are damaged or obstructed. Since another iPhone is recognized on the same computer, the issue is isolated to the original iPhone's Lightning port. The 'Trust This Computer' prompt appearing and being accepted confirms that the software trust relationship is not the problem, further pointing to a hardware data pin failure.

Answer

The iPhone's battery needs to be replaced.

Answer

The iPhone's operating system is corrupt.

Answer

The iPhone's display assembly is malfunctioning.

Question 2

A user reports that their Android smartphone's screen is cracked in the lower-left corner. The touch input in that area is unresponsive, but the display works correctly and the rest of the touchscreen functions normally. Which of the following is the BEST repair option?

Accepted Answer

C. Replace the entire screen assembly (LCD and digitizer combined). In modern smartphones, the digitizer (touch layer) and LCD panel are fused together into a single screen assembly. When the glass is cracked and touch input is lost in a specific area, the digitizer is damaged, but separating it from the LCD is impractical and risks further damage. Replacing the entire screen assembly ensures both the display and touch functionality are restored reliably.

Answer

A. Replace only the digitizer (touch layer)

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B. Replace only the LCD panel

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D. Apply a tempered glass screen protector

Question 3

A user reports that their Android smartphone's battery drains very quickly during normal use and the phone feels unusually warm, especially near the back panel. The technician has already tested the charging cable and power adapter with another device and they work correctly. Which of the following components is MOST likely faulty?

Accepted Answer

Battery. The battery is the most likely faulty component because rapid drainage and excessive heat generation, particularly near the back panel where the battery is typically located, are classic symptoms of a degraded or internally shorted lithium-ion battery. A failing battery can have increased internal resistance, causing it to discharge quickly and convert electrical energy into heat rather than storing it properly.

Answer

Charging port/board

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Screen

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CPU/SoC

Question 4

A technician is replacing the battery in an Android smartphone. Which of the following is the MOST important step to prevent damage to the SIM card during the repair?

Accepted Answer

Remove the SIM card tray. The SIM card is a delicate component that can be easily damaged if the phone is opened without first removing it. By taking out the SIM card tray, you eliminate the risk of bending or scratching the SIM card when prying the battery or handling internal components. This step is critical because the SIM card sits on a flexible tray that can snap or warp under pressure, potentially rendering the card unusable.

Answer

Power off the phone

Answer

Use a plastic spudger to pry the battery

Answer

Disconnect the screen flex cable

Question 5

A user reports that their iPhone screen is cracked in the bottom-left corner. The display works correctly, but the touch input in the cracked area is unresponsive. The rest of the touchscreen functions normally. Which of the following is the BEST repair option?

Accepted Answer

Replace the complete screen assembly. The iPhone uses a fused display assembly where the LCD, digitizer, and glass are bonded together. Since the digitizer (touch layer) is damaged in the cracked area, replacing only the digitizer is not practical without specialized equipment to separate it from the LCD. Replacing the complete screen assembly restores both display and touch functionality, making it the best option.

Answer

Replace only the digitizer

Answer

Replace only the LCD

Answer

Apply a tempered glass screen protector

Question 6

A user brings in an iPhone that will not turn on. The technician has verified that the charging cable and power adapter work correctly by testing them with another iPhone. The technician attempts a force restart by pressing and holding the Side and Volume Down buttons, but the device remains unresponsive. Which of the following is the MOST likely cause of the issue?

Accepted Answer

Battery is completely discharged. The iPhone remains unresponsive even after a force restart, but the charging cable and adapter work with another device. This indicates the battery is completely discharged below the threshold required to initiate charging or power-on. Lithium-ion batteries have a protection circuit that can enter deep discharge mode, requiring a period of charging before the device will respond to any button presses.

Answer

Faulty power button

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Water damage

Answer

Logic board failure

Question 7

A user reports that their Android smartphone will not charge. The technician tries a different charging cable and wall adapter, but the phone still does not charge. The USB port on the phone appears clean and free of debris. Which of the following components is MOST likely faulty and should be replaced?

Accepted Answer

Charging port flex cable. The charging port flex cable is the most likely faulty component because the technician has already ruled out external factors (cable and wall adapter) and the USB port appears clean. The flex cable connects the USB port to the phone's motherboard, and internal damage or wear to this cable can interrupt power delivery even when the port itself looks fine. Replacing the flex cable is a common repair for charging issues that persist after basic troubleshooting.

Answer

Battery

Answer

Screen

Answer

Processor

Question 8

A user's iPhone 12 has no sound from the speaker during phone calls, but the earpiece works normally. The user has confirmed that the volume is turned up and the silent switch is not enabled. The technician has performed a restart and updated iOS to the latest version. Which of the following is the MOST likely cause of the issue?

Accepted Answer

The speaker grille is blocked or the speaker is faulty. The iPhone 12 uses a separate earpiece speaker for phone calls and a bottom-firing speaker for media and speakerphone. Since the earpiece works but the main speaker has no sound during calls, the issue is isolated to the bottom speaker grille being blocked (e.g., by debris or case obstruction) or the speaker itself being faulty. Restarting and updating iOS rules out software glitches, making hardware blockage or failure the most likely cause.

Answer

The Lightning port is clogged

Answer

The SIM card is damaged

Answer

The screen is cracked

Question 9

A user reports that their Android smartphone's battery drains very quickly, even when the phone is idle. The phone also feels unusually warm near the back cover. The technician has already checked that no apps are running abnormally in the background and the screen brightness is set to auto. Which component is MOST likely faulty?

Accepted Answer

Battery. The battery is the most likely faulty component because a degraded or internally shorted lithium-ion battery can cause rapid self-discharge and excessive heat generation even when the device is idle. The technician has already ruled out abnormal background apps and screen brightness, which isolates the issue to the battery's internal chemistry or protection circuit.

Answer

Charging port

Answer

Display screen

Answer

Processor (SoC)

Question 10

A user reports that their laptop's battery indicator shows 'plugged in, not charging.' The technician tests the AC adapter with a multimeter and verifies it outputs the correct voltage. The laptop is a standard model with a removable battery. Which of the following components is MOST likely faulty?

Accepted Answer

Battery. The battery indicator showing 'plugged in, not charging' with a verified good AC adapter strongly points to a faulty battery. Since the adapter outputs correct voltage, the laptop detects the external power source (hence 'plugged in') but the battery itself cannot accept a charge, often due to degraded cells or failed internal protection circuitry. A removable battery is a common failure point, especially in older or heavily used laptops.

Answer

DC power jack

Answer

Motherboard charging circuit

Answer

Power management IC

Question 11

A technician replaced the cracked screen on an iPhone 11. After reassembling the device, the phone powers on and responds to touch, but the display remains black. The technician hears the camera shutter sound when tapping the camera icon. Which of the following is the MOST likely cause?

Accepted Answer

The display cable is not connected properly. The iPhone 11 uses a single display assembly cable that carries both the LCD data and the digitizer (touch) signals. If the display cable is not fully seated or is damaged, the phone may still power on and register touch input (because the digitizer portion of the cable has partial contact), but the LCD backlight or data lines may be interrupted, resulting in a black screen. The camera shutter sound confirms the device is operational and the logic board is functioning, isolating the issue to the display connection.

Answer

The battery connector is loose

Answer

The front camera flex cable is damaged

Answer

The motherboard was damaged during the repair

Question 12

A user reports that their Android smartphone displays 'No SIM card - Emergency calls only' even though the SIM is properly inserted. The technician removes the SIM and inserts it into another compatible phone, where it works perfectly. The technician then inserts a known-working SIM from another phone into the original device, which still shows 'No SIM card.' Which of the following is the MOST likely cause?

Accepted Answer

The SIM slot contacts are damaged or dirty. Since the known-working SIM also fails in the original device, the fault is isolated to the device's SIM interface. Damaged or dirty SIM slot contacts can prevent the electrical connection needed for the phone to detect the SIM, even though the SIM itself is functional. This is the most likely cause because the SIM works in another phone and the original phone fails with any SIM.

Answer

The SIM card tray is upside down

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The IMEI number is corrupted in software

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The phone's baseband firmware needs to be updated

Question 13

A user reports that their smartphone's screen appears to be slightly bulging outward and the back cover is separating from the chassis. The phone still powers on and functions normally. Which of the following components is MOST likely causing this issue?

Accepted Answer

Battery. A bulging screen and separating back cover are classic signs of a swollen lithium-ion battery. As the battery degrades, internal chemical reactions produce gas, causing the battery casing to swell and physically push against the phone's chassis. This occurs even if the phone still powers on and functions normally, as the battery can still deliver voltage while its physical integrity is compromised.

Answer

Digitizer

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LCD panel

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Charging port

Question 14

A user reports that their smartphone will not charge when plugged into a wall outlet, even though the charging cable appears undamaged and the outlet works with other devices. Which of the following is the MOST likely cause of this issue?

Accepted Answer

Dirt or lint is blocking the charging port.. The most likely cause is dirt or lint blocking the charging port. When debris accumulates in the port, it can prevent the charging cable from making proper electrical contact with the pins, even though the cable and outlet are functional. This is a common issue with smartphones due to pocket lint or dust, and it typically does not require a battery or system replacement.

Answer

The battery has reached the end of its life and must be replaced.

Answer

The operating system has corrupted system files preventing charging.

Answer

The user is using a charger with insufficient wattage for this phone model.

Question 15

A user reports that their smartphone will not charge when connected to a USB port on their laptop, but it charges fine when plugged into a wall charger. The laptop's other USB ports work with a mouse and keyboard. Which of the following is the MOST likely cause?

Accepted Answer

Laptop USB port power output is too low. The most likely cause is that the laptop's USB port does not provide enough power to charge the smartphone. USB 2.0 ports typically supply up to 500 mA, while many modern smartphones require 1 A or more for charging. The wall charger can supply higher current, which is why charging works there. The fact that the mouse and keyboard work confirms the port is functional for low-power devices.

Answer

Faulty USB cable

Answer

Smartphone's battery is defective

Answer

Laptop USB drivers are outdated