220-1101 Mobile Devices Practice Test 11 — 15 Questions

Question 1

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 2

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 3

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 4

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

Answer

A defective battery

Answer

Malware infection

Question 5

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 6

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 7

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 8

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. When Bluetooth fails to enable and the toggle immediately reverts, it often indicates a driver or firmware issue. The first step in troubleshooting should be to restart the device, as this clears temporary software glitches. If that does not work, checking for OS updates is the next step, as updates often include driver fixes. Replacing the battery is unlikely to help unless the battery is swollen (which would usually cause other symptoms). Resetting network settings is a more invasive step that should be done after trying a simple restart and updates.

Answer

Replace the battery

Answer

Check for operating system updates

Answer

Reset network settings

Question 9

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 10

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 11

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 12

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

Question 13

A user reports that their smartphone's touch screen stopped working after the phone was briefly submerged in water. The technician dried the device thoroughly, then replaced the screen assembly (including the digitizer) with a known-good part. After reassembly, the touch screen is still completely unresponsive. The display works correctly, and the phone powers on and charges normally. Which of the following components should the technician check next?

Accepted Answer

The motherboard's touch screen controller IC. Water damage can short or corrode the touch screen controller IC on the motherboard, which processes signals from the digitizer. Since the display and other functions work, the issue is isolated to the touch input path, and replacing the screen assembly (including the digitizer) did not resolve it, pointing to a damaged controller IC rather than the peripheral components.

Answer

The battery

Answer

The charging port

Answer

The SIM card slot

Question 14

A user reports that their smartphone's battery life has significantly decreased after a recent OS update. The technician observes that location services and background app refresh are enabled. Which of the following should the technician do FIRST to address the issue?

Accepted Answer

Check the battery health status in the device settings. Before taking more invasive steps such as disabling all background processes or performing a factory reset, the technician should first check the battery health status in the device settings. Modern smartphones include a battery health feature that indicates the maximum capacity and whether the battery needs to be replaced. This helps determine if the battery is physically degraded, which could be the root cause of poor battery life, especially after an OS update that may have changed power management. If the battery health is good, then software settings like location services or background app refresh can be adjusted.

Answer

Calibrate the battery by fully draining it and then charging it to 100%

Answer

Disable all background app refresh settings

Answer

Perform a factory reset of the smartphone

Question 15

A user's smartphone is unable to make or receive calls. The device shows full signal bars but when attempting to place a call, it immediately ends. The technician checks airplane mode and it is off. Which of the following should the technician check FIRST?

Accepted Answer

Check the SIM card.. Full signal bars indicate the device is connected to the cellular network at the RF level, but an immediate call failure suggests the device cannot register with the network for voice services. The SIM card contains the IMSI and authentication keys (Ki) required for network registration; if it is loose, damaged, or not properly seated, the phone will show signal bars from the base station but fail to complete call setup because the network rejects the unauthenticated device.

Answer

Reboot the phone.

Answer

Check the Bluetooth settings.

Answer

Check the Wi-Fi calling settings.