220-1101 Question 15
Single answerUniversal Serial Bus (USB)/USB-C/microUSB/miniUSBA technician is helping a user connect a newer laptop to an external 4K monitor and a USB docking station. The laptop has two USB-C ports. When the technician uses a basic USB-C charging cable that was available at the front desk, the dock powers on and the user's phone charges, but the monitor connected through the dock does not display any video. The dock and monitor are known to work with another laptop. Which action should the technician take FIRST to resolve the issue?
- A
Replace the cable with a USB-C cable that supports data and video, such as one rated for DisplayPort Alt Mode or Thunderbolt
- B
Replace the monitor with one that has a native USB-C input instead of HDMI or DisplayPort
- C
Use a microUSB-to-USB-C adapter so the dock can negotiate video output correctly
- D
Install a USB 2.0 driver package on the laptop so the USB-C port can transmit display signals
Show answer and explanation
Correct answer: A
Explanation
This scenario tests a key A+ Core 1 concept: USB-C describes the connector shape, not a guaranteed feature set. In real-world troubleshooting, technicians must confirm whether the port and cable support the needed capabilities, such as USB data, power delivery, DisplayPort Alt Mode, or Thunderbolt. A common mistake is assuming any USB-C cable can carry video. In this case, the fact that the dock powers on and other USB-related functions work suggests that basic power and possibly data are available, but video is not. That points first to the cable or feature support rather than the monitor itself. Best practice is to verify the dock requirements and use a known-good, full-featured USB-C cable that explicitly supports video output. This aligns with manufacturer documentation for USB-C docks and with USB-IF and vendor guidance that USB-C cables can vary significantly in capability.
- A. Correct.
Correct. Not all USB-C cables support the same features. Some USB-C cables are charge-only or support limited USB data rates and do not carry video. Many docks require a full-featured USB-C cable that supports data plus DisplayPort Alt Mode, and some docks may require Thunderbolt-capable connectivity depending on the dock design. Since power is working but external display output is not, the cable is the most likely first item to verify and replace.
- B. Incorrect.
Incorrect. The monitor is already known to work with the dock and another laptop, so replacing the monitor is unnecessary and does not address the likely root cause. USB-C docks commonly output video to monitors over HDMI or DisplayPort without requiring the monitor itself to have a USB-C input.
- C. Incorrect.
Incorrect. microUSB does not provide the modern USB-C alternate mode functionality used for video output from typical USB-C docks. Using a microUSB adapter would not enable DisplayPort Alt Mode and is not an appropriate troubleshooting step for this scenario.
- D. Incorrect.
Incorrect. USB-C video output is not enabled by installing a USB 2.0 driver package. Video over USB-C typically depends on hardware support in the port, the dock, and the cable, along with the system's graphics and chipset drivers where applicable. A generic USB 2.0 driver would not resolve a missing video signal caused by an insufficient cable.