220-1101 Mobile Devices Troubleshooting — 20 Questions

Question 1

A user reports that their iPhone 13 will not charge when plugged into the charging port. The user has tried different cables and power adapters, but the phone still does not charge. The phone's screen and buttons work normally. Which of the following is the most likely cause?

Accepted Answer

The Lightning port is clogged with debris. Since the user has already ruled out the cable and adapter, the issue is likely with the phone itself. A common problem is debris or lint compacted in the Lightning port, preventing a proper connection. Cleaning the port carefully can often resolve this.

Answer

The battery is completely dead and needs replacement

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The operating system is corrupted

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The phone's wireless charging coil is damaged

Question 2

A user reports that their smartphone's screen is flickering and has vertical lines. The phone has not been dropped or exposed to water. Which of the following is the most likely cause of this issue?

Accepted Answer

The display cable is loose or damaged. Screen flickering and vertical lines are classic symptoms of a failing display or a loose internal display cable. Since there was no physical trauma, a loose connection or a manufacturing defect in the display assembly is the most probable cause.

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A software glitch caused by a recent app update

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The battery is swelling and pressing against the display

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The phone's processor is overheating

Question 3

A technician is troubleshooting a laptop that powers on but displays a black screen with no boot activity. The technician hears the fan spinning and sees the power LED is on. Which of the following steps should the technician perform next to isolate the issue?

Accepted Answer

Connect an external monitor. A black screen with power but no boot suggests a hardware issue, often with the display or memory. Connecting an external monitor can quickly determine if the problem is with the laptop's LCD panel or the video output. If the external monitor works, the internal display or its cable is likely faulty.

Answer

Reseat the RAM modules

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Replace the LCD panel

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Reinstall the operating system

Question 4

A user complains that their laptop's Wi-Fi connection is extremely slow and keeps dropping, but other devices on the same network work fine. The laptop is an older model running Windows 10. Which of the following should the technician try first?

Accepted Answer

Update the Wi-Fi driver. An outdated or corrupted Wi-Fi driver is a common cause of connectivity issues on older laptops. Updating the driver is a software-level fix that is quick and non-invasive, and it often resolves intermittent connectivity problems.

Answer

Replace the laptop's Wi-Fi card

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Disable the firewall

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Reset the router

Question 5

A technician is troubleshooting a laptop that has a blinking battery light and will not power on, even when plugged into AC power. The technician has already verified the AC adapter is working on another laptop. Which component is most likely faulty?

Accepted Answer

The battery. A blinking battery light often indicates a battery or charging circuit error. Since the AC adapter is known to be good, the issue is likely with the laptop's internal battery, the DC jack, or the charging circuit on the motherboard. The battery is the most common failure point.

Answer

The CPU

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The RAM

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The hard drive

Question 6

A technician is configuring a new Android tablet for a warehouse employee. The employee will use the tablet to scan barcodes and access a web-based inventory system. The tablet needs to stay connected to the Wi-Fi network even when the screen is off to receive updates. Which setting should the technician configure?

Accepted Answer

Enable 'Keep Wi-Fi on during sleep' and set it to 'Always'. Android devices have a power-saving feature that disconnects Wi-Fi when the screen is off to save battery. To ensure the tablet stays connected, the technician must change the 'Keep Wi-Fi on during sleep' setting to 'Always'.

Answer

Set the screen timeout to 30 minutes

Answer

Disable Bluetooth

Answer

Install a third-party app to keep the screen on

Question 7

A customer brings in a tablet that will not turn on. The technician presses the power button and sees no response. The tablet was working earlier in the day. What is the first step the technician should take to troubleshoot this issue?

Accepted Answer

Connect the tablet to a charger and wait a few minutes. The most logical first step is to ensure the device has power; a drained battery is a common cause of a device not turning on. Checking the charge level and attempting to charge it is a simple, non-invasive test that can quickly identify the problem.

Answer

Replace the battery immediately

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Perform a hard reset by holding the power and volume buttons

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Open the tablet and inspect the motherboard for damage

Question 8

A user reports that their laptop's touchpad is not working properly. The cursor jumps around randomly when they try to use the touchpad. An external mouse works fine. Which of the following should the technician do first?

Accepted Answer

Clean the touchpad surface with a soft cloth. Cursor jumping is often caused by a dirty or greasy touchpad surface. Cleaning the touchpad with a soft, lint-free cloth is the simplest and most effective first step before considering driver or hardware issues.

Answer

Update the touchpad driver

Answer

Disable the touchpad in Device Manager and re-enable it

Answer

Replace the touchpad

Question 9

A user reports that their smartphone's battery drains very quickly, even when the phone is idle. The phone is less than a year old. Which of the following is the most likely cause of this issue?

Accepted Answer

An app is running in the background and consuming power. A common cause of rapid battery drain on smartphones is apps running in the background, especially after an OS update that may change permissions or app behavior. Checking battery usage statistics can help identify the culprit.

Answer

The battery is defective and needs replacement

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The screen brightness is set too high

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The phone is infected with a virus

Question 10

A user reports that their Android smartphone's touchscreen is unresponsive after they dropped it. The screen is not cracked, and the device powers on normally. Which of the following is the most likely cause of the touchscreen issue?

Accepted Answer

The digitizer is damaged. A drop can easily damage the digitizer layer, which is responsible for detecting touch input, even if the glass display remains intact. The LCD/OLED panel may still function for display, but without a working digitizer, touch input will not register.

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The LCD panel is damaged

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The battery is swollen

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The operating system is corrupted

Question 11

A user reports that their iPhone 12 will not turn on after being left in a hot car for several hours. The device feels warm, and pressing the power button does nothing. What is the most likely cause of the device not powering on?

Accepted Answer

The device entered a thermal shutdown state to protect internal components. Excessive heat can trigger thermal protection circuits in modern smartphones, causing them to shut down and refuse to power on until they cool down. This is a safety feature to prevent battery or component damage. The correct answer identifies thermal shutdown as the cause.

Answer

The battery has expanded due to heat and disconnected from the logic board

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The device's logic board has been permanently damaged by heat

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The power button is stuck due to heat expansion

Question 12

A customer brings in a laptop that will not charge. The technician checks the AC adapter with a multimeter and gets 19V output. When the adapter is plugged into the laptop, the charging LED does not illuminate. What should the technician check next?

Accepted Answer

Test the DC jack for continuity. Since the AC adapter is outputting correct voltage, the issue is likely in the power delivery path. The DC jack is a common failure point due to mechanical stress or broken solder joints. Testing continuity at the jack is a logical next step.

Answer

Replace the laptop's battery

Answer

Update the laptop's BIOS

Answer

Replace the AC adapter with a universal one

Question 13

A user reports that their laptop's touchpad is not working after they spilt a small amount of coffee on the keyboard. The keyboard still works, but the touchpad cursor does not move. What is the most likely cause?

Accepted Answer

The liquid has damaged the touchpad or its ribbon cable. Coffee can seep into the touchpad connector or the touchpad itself, causing a short or corrosion. The keyboard working suggests the liquid did not reach the main board, but the touchpad is a separate component that is more exposed. The correct answer is liquid damage to the touchpad.

Answer

The touchpad driver has been corrupted by the liquid

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The touchpad has been disabled in the BIOS due to a safety feature

Answer

The laptop's operating system has detected the liquid and disabled input devices

Question 14

A user reports that their Windows tablet's battery drains quickly even when the device is idle. The technician checks the battery report and finds that the 'System' process is using a high percentage of CPU. What is the most likely cause?

Accepted Answer

A device driver is preventing the tablet from entering a low-power sleep state. High CPU usage by the 'System' process often indicates a driver or hardware issue, such as a failing battery or a misconfigured power plan. In tablets, a common cause is a driver that prevents the device from entering low-power sleep states, leading to constant CPU activity and battery drain.

Answer

The battery is nearing the end of its life and cannot hold a charge

Answer

A background app is consuming CPU resources

Answer

The tablet's power plan is set to 'High performance'

Question 15

A technician is configuring a new Android tablet for a field worker. The worker will use a Bluetooth barcode scanner and a rugged case with a built-in keyboard. After pairing both devices, the keyboard types slowly and misses keystrokes, while the scanner works fine. What is the most likely cause?

Accepted Answer

Interference from the rugged case or other wireless signals is degrading the keyboard's connection. Bluetooth interference from other devices or physical obstructions (like a rugged case) can cause signal degradation, leading to missed keystrokes. The scanner may use a different Bluetooth profile or be less sensitive to interference. The correct answer identifies interference as the likely cause.

Answer

The keyboard's battery is low

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The tablet's Bluetooth driver is outdated

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The keyboard is not compatible with Android

Question 16

A technician is troubleshooting a laptop that emits a series of beeps (one long, two short) on startup and displays nothing on the screen. The laptop was working fine until the user installed a new RAM module. What is the most likely cause?

Accepted Answer

The new RAM module is incompatible with the laptop's chipset. One long and two short beeps is a common BIOS POST code indicating a video or display adapter issue. However, since the problem started after installing RAM, it is likely that the RAM module is incompatible or not seated properly, causing a memory-related POST failure that manifests as a video error code on some systems.

Answer

The laptop's display cable has become disconnected

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The laptop's CMOS battery is dead

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The user accidentally damaged the motherboard when installing the RAM

Question 17

A user complains that their laptop's built-in webcam is not working in video conferencing apps. The device manager shows the camera as 'disabled'. The technician enables it, but the camera still shows a black screen in apps. What should the technician do next?

Accepted Answer

Check for a physical privacy shutter on the webcam and verify Windows camera privacy settings. Even if the camera is enabled in Device Manager, the privacy shutter or a privacy setting in the OS (like Windows Camera privacy settings) can block the camera. Checking the physical shutter and OS privacy settings is the logical next step.

Answer

Uninstall and reinstall the camera driver

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Replace the webcam module

Answer

Update the laptop's BIOS

Question 18

A user reports that their Android smartphone's touchscreen is unresponsive after they dropped it in a puddle. The device powers on, but the display shows distorted colors and the touch input does not register at all. What is the most likely cause of this issue?

Accepted Answer

The digitizer and LCD have been damaged by liquid ingress. Water damage can cause short circuits and corrosion on the display digitizer and LCD panel, leading to both touch unresponsiveness and visual distortion. Powering on a wet device often worsens the damage. The correct answer focuses on the digitizer and LCD failure due to liquid ingress.

Answer

The device's battery is swollen and pressing against the display

Answer

The device's operating system has corrupted due to water exposure

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The screen protector is trapping moisture and blocking touch input

Question 19

A technician is troubleshooting a laptop that has a blank screen after the user closed the lid and then reopened it. The laptop's power LED is on, and the fan is spinning. Pressing keys does not wake the display. What should the technician do first?

Accepted Answer

Perform a hard reset by holding the power button for 10-15 seconds. This scenario describes a classic 'lid sensor' or 'display not waking' issue. The laptop is on (power LED, fan), but the display is blank. The first step should be to perform a hard reset by holding the power button to force a shutdown, then power on again. This can clear a hung state.

Answer

Replace the LCD panel

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Reseat the RAM modules

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Check the laptop's lid sensor for damage

Question 20

A technician is troubleshooting a Samsung Galaxy tablet that has a cracked screen but still responds to touch. The user wants to transfer data to a new tablet. The technician connects the tablet to a PC via USB, but the PC does not recognize the device. What is the most likely reason?

Accepted Answer

The tablet is in USB charging-only mode and cannot be changed due to the cracked screen. When a device's screen is cracked, the digitizer may still work, but the user might not be able to change USB settings from 'Charging only' to 'File transfer' if the touch input is needed for that selection. This is a common scenario where the default USB mode prevents data access.

Answer

The USB cable is defective

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The tablet's USB port is damaged from the drop

Answer

The PC lacks the proper Samsung USB drivers