220-1101 Mobile Devices Practice Test 11 — 15 Questions

Question 1

A user reports that their smartphone Wi-Fi connection at home frequently drops when they move from one room to another. The home has a single wireless router located in the basement. Which of the following is the MOST likely cause of the intermittent connection?

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

Accepted Answer

The phone is configured to use only the 5 GHz band.. The 5 GHz band has shorter range and poorer penetration through walls and floors compared to the 2.4 GHz band. When the user moves between rooms, the signal from the basement router may drop below the threshold required for a stable 5 GHz connection, causing intermittent disconnects. The phone being locked to 5 GHz prevents it from falling back to the more robust 2.4 GHz band.

Answer

The phone's Bluetooth is interfering with Wi-Fi.

Answer

The router's firmware is outdated.

Answer

Too many devices are connected to the router.

Question 2

A technician is repairing a smartphone that has a cracked screen. The glass is shattered but the LCD and digitizer underneath are functional except for unresponsive touch in some areas. The user wants all data preserved. After disconnecting the battery, which tool is MOST critical for safely lifting the cracked glass to access the internal components?

Accepted Answer

Suction cup. The suction cup is the most critical tool for safely lifting the shattered glass because it provides a controlled, even pulling force to separate the glass from the frame without further damaging the underlying LCD and digitizer. Since the glass is cracked but the LCD and digitizer are still functional, using a suction cup minimizes the risk of applying uneven pressure that could crack the LCD or tear the digitizer flex cables. This tool is essential for preserving data by avoiding additional damage to the display assembly during disassembly.

Answer

Screwdriver set

Answer

Spudger

Answer

Magnifying glass

Question 3

A user wants to connect their smartphone to an external monitor for a presentation. The monitor only has a VGA input, and the smartphone has a USB-C port that supports DisplayPort Alt Mode. Which cable or adapter should the user obtain to connect the devices?

Accepted Answer

USB-C to VGA adapter. The monitor only has a VGA input, which is an analog video interface. The smartphone's USB-C port supports DisplayPort Alt Mode, which can output a digital DisplayPort signal. A USB-C to VGA adapter contains a digital-to-analog converter (DAC) that converts the DisplayPort signal from the phone into an analog VGA signal compatible with the monitor.

Answer

USB-C to HDMI adapter

Answer

USB-C to DisplayPort cable

Answer

Thunderbolt 3 to VGA cable

Question 4

A user's smartphone is connected to a Wi-Fi network but cannot send or receive email. The user can browse the internet using the web browser. Which of the following is the MOST likely cause?

Accepted Answer

The smartphone's date and time settings are incorrect. The smartphone can browse the internet, indicating that the Wi-Fi connection and general internet access are working. Email protocols (IMAP, POP3, SMTP) rely on TLS/SSL certificates for secure connections, and these certificates are validated against the device's system clock. If the date and time are incorrect, the certificate validation fails, preventing the email client from establishing a secure connection to the email server, even though basic web browsing (which may use less strict certificate checks or cached content) still works.

Answer

The email server is offline

Answer

The email account password has changed

Answer

The Wi-Fi signal is weak

Question 5

A technician is replacing the battery in a smartphone. After reassembly, the phone powers on and the screen works, but the battery icon shows 0% charge and the phone does not recognize the battery. The technician verifies that the battery connector is fully seated. Which of the following should the technician check NEXT?

Accepted Answer

The flex cable connecting the battery to the motherboard is damaged. The battery connector being fully seated does not rule out damage to the flex cable itself. A damaged flex cable can cause an open circuit or intermittent connection between the battery and the motherboard, preventing the battery management system from reading the battery's charge level or identification data, even though the phone powers on via residual charge or a direct power path.

Answer

The battery is defective and needs to be replaced

Answer

The charging port is damaged

Answer

The battery management chip is faulty

Question 6

A user reports that their smartphone will not power on. When they plug it into a charger, the LED indicator flashes red but the screen remains black. The phone was working normally earlier in the day and was not dropped or exposed to water. Which of the following is the MOST likely cause?

Accepted Answer

Faulty battery. The LED indicator flashing red when the charger is connected, combined with a black screen and no prior physical damage or water exposure, strongly points to a battery that has entered a deep discharge state or has failed. In this scenario, the battery cannot hold enough charge to power the phone's boot sequence, but the charging circuit can still detect the charger and attempt to charge, causing the red LED. A faulty battery is the most common cause of a device that was working normally and then suddenly will not power on, especially when the screen remains black but the LED responds.

Answer

Damaged screen

Answer

Failed CPU

Answer

Corrupted firmware

Question 7

A user reports that their smartphone's battery drains very quickly and the phone feels hot to the touch, even when the phone is idle. The phone is running the latest version of its operating system. Which of the following is the MOST likely cause?

Accepted Answer

A background app using excessive CPU resources. A background app using excessive CPU resources is the most likely cause because high CPU utilization generates significant heat and drains the battery rapidly, even when the phone is idle. The phone's operating system may not effectively throttle such rogue processes, especially if the app is poorly optimized or stuck in a loop. This symptom pattern—heat plus rapid discharge without active use—is classic for a runaway CPU process.

Answer

A faulty charging cable

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A defective battery

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Malware infection

Question 8

A user's smartphone will not charge when plugged into a cable. The technician inspects the charging port and finds it is clean and the cable appears undamaged. The phone was working normally earlier and was not dropped. The technician tests the cable with another device and it charges normally. Which of the following should the technician do NEXT to diagnose the issue?

Accepted Answer

Test the phone with a different, known-good charger and cable. Since the cable works with another device and the charging port is clean, the issue is isolated to the phone's charging circuit or battery management system. Testing with a known-good charger and cable eliminates variables and confirms whether the phone itself is rejecting power, which is the standard next step in CompTIA A+ troubleshooting methodology.

Answer

Replace the battery with a new one

Answer

Perform a factory reset of the smartphone

Answer

Replace the charging port assembly

Question 9

A technician replaced the screen assembly on a smartphone. After reassembly, the phone powers on and displays correctly, but the touch screen is unresponsive. Which of the following should the technician check FIRST?

Accepted Answer

Ensure the digitizer ribbon cable is properly seated. The digitizer ribbon cable connects the touch-sensitive layer of the screen to the motherboard. If it is loose or improperly seated after reassembly, the touch input cannot be registered even though the display (LCD/OLED) works fine. This is the most likely cause given the recent disassembly and should be checked first before any software or replacement steps.

Answer

Reboot the phone into safe mode

Answer

Update the touch screen drivers

Answer

Replace the screen assembly again

Question 10

A user's smartphone screen is cracked and the touch is unresponsive in the cracked area. The technician replaces the screen assembly. After reassembly, the phone powers on, displays correctly, but the touch still does not work in the same area. What should the technician check first?

Accepted Answer

Digitizer cable connection. The digitizer is the component responsible for touch input, and it connects to the mainboard via a separate cable from the LCD. If the touch remains unresponsive in the same area after replacing the screen assembly, the most likely cause is a loose, damaged, or improperly seated digitizer cable connection. The display works correctly, which confirms the LCD cable is fine, isolating the issue to the digitizer.

Answer

LCD cable connection

Answer

Battery connection

Answer

Proximity sensor

Question 11

A user reports that their smartphone's Bluetooth will not enable. When the user taps the Bluetooth toggle in the Quick Settings panel, it briefly turns blue and then immediately turns gray. The phone did not get wet and was not dropped recently. Which of the following should the technician check FIRST?

Accepted Answer

Restart the smartphone. A Bluetooth toggle that briefly turns on then immediately reverts to gray typically indicates a software or firmware state issue, and the first, least invasive troubleshooting step is to restart the smartphone. A reboot clears stuck Bluetooth stack states, resets the radio, and resolves most transient toggle failures. CompTIA's troubleshooting methodology prioritizes simple, non-destructive steps first.

Answer

Replace the battery

Answer

Check for operating system updates

Answer

Reset network settings

Question 12

A technician replaces the digitizer on a smartphone that had a cracked screen and an unresponsive touch area. After reassembly, the touch screen still does not respond in the area where the crack was. The technician has already verified that all flex cable connections to the digitizer are secure. Which of the following should the technician do NEXT?

Accepted Answer

Test the phone with a known-good digitizer. The technician has already verified that all flex cable connections to the digitizer are secure, yet the touch screen remains unresponsive in the same area. This indicates the replacement digitizer itself may be defective. Testing with a known-good digitizer isolates the issue to the digitizer component versus the phone's main board or software, following a logical hardware troubleshooting process.

Answer

Replace the LCD assembly

Answer

Calibrate the touch screen in the operating system

Answer

Update the phone's firmware

Question 13

A user reports that their smartphone’s battery drains very quickly, even when not actively in use. The technician notes that the device feels warm to the touch, the screen brightness is set to maximum, and several apps are running in the background. The device is running the latest OS version. Which of the following should the technician recommend as the FIRST step to address the battery drain?

Accepted Answer

Reduce the screen brightness and close unused background apps. The most immediate and effective first step is to reduce screen brightness and close unused background apps because the display is the largest power consumer in a smartphone, and background apps can keep the CPU active, generating heat and draining the battery. Since the device is already on the latest OS version and the symptoms point to user-configurable settings rather than hardware failure, this non-invasive step directly addresses the two most likely causes of rapid drain.

Answer

Replace the battery with a new OEM battery

Answer

Perform a factory reset and restore from a recent backup

Answer

Update the device’s operating system

Question 14

A user reports that their smartphone battery percentage jumps erratically—for example, showing 50% then suddenly dropping to 10% and shutting down. The technician verifies the battery is not swollen, the charging port is clean, and the device charges normally. Which of the following should the technician try NEXT?

Accepted Answer

Calibrate the battery. The erratic battery percentage drop without physical swelling or charging issues indicates a software calibration problem, not a hardware failure. Calibrating the battery resets the fuel gauge chip's learned capacity values, allowing the operating system to accurately report charge levels. This is the correct next step before replacing the battery.

Answer

Replace the battery

Answer

Update firmware

Answer

Replace the charging port

Question 15

A user wants to synchronize their smartphone's contacts and calendar with their company's Microsoft Exchange server. Which protocol is specifically designed to provide this synchronization?

Accepted Answer

Exchange ActiveSync. Exchange ActiveSync (EAS) is a Microsoft protocol specifically designed to synchronize email, contacts, calendar, tasks, and notes between mobile devices and an Exchange server. It uses HTTP(S) and supports push synchronization, remote wipe, and policy enforcement, making it the correct choice for syncing contacts and calendar with a company's Exchange environment.

Answer

IMAP

Answer

POP3

Answer

SMTP