220-1101 Question 392
Single answerBurning smellA technician is called to look at a desktop PC that shut down unexpectedly during normal use. When the user tried to turn it back on, the technician noticed a strong burning smell coming from the rear exhaust area of the case. What should the technician do FIRST?
- A
Power off the system, unplug it from AC power, and inspect the power supply and internal components for signs of damage before attempting further startup
- B
Restart the computer and enter the BIOS/UEFI to check the temperature readings for the CPU and motherboard
- C
Open the case while the system remains plugged in so the technician can quickly identify which fan has failed
- D
Replace the operating system because corrupted system files can cause overheating and a burning odor
Show answer and explanation
Correct answer: A
Explanation
The best first action is to remove power and inspect the system safely. In CompTIA A+ Core 1 troubleshooting, a burning smell is a classic symptom of hardware failure, commonly associated with the power supply unit (PSU), damaged wiring, shorted boards, overheated connectors, or failed fans that have allowed components to overheat. Standard technician best practices are to protect people and equipment first: power down the device, unplug it, and look for visible signs such as scorch marks, melted plastic, discolored connectors, or seized fans. The technician should not continue powering on the system until the source of the odor is identified. This aligns with general electrical safety practices and CompTIA hardware troubleshooting methodology, where potentially dangerous symptoms are addressed before further testing.
- A. Correct.
Correct. A burning smell indicates a potential electrical failure, such as a failing power supply, shorted component, melted insulation, or overheating connector. The first priority is safety: shut the system down if it is still on, disconnect AC power, and inspect for visible damage before applying power again. On A+ Core 1, a burning smell is treated as a hardware troubleshooting and safety issue, not a software problem.
- B. Incorrect.
Incorrect. Checking BIOS/UEFI temperature readings may be useful later if the system can be powered on safely, but a burning smell suggests possible immediate hardware damage or electrical hazard. Attempting to restart the system before inspection could worsen component failure or create a fire risk.
- C. Incorrect.
Incorrect. Opening the case while the system is still plugged in is unsafe. Even when a computer is off, the power supply can still provide standby voltage, and the PSU itself contains components that can retain dangerous charge. The correct first step is to disconnect power before inspecting hardware.
- D. Incorrect.
Incorrect. An operating system problem does not create a true burning odor from the rear of the case. This option reflects a common misconception of blaming software for symptoms that clearly point to hardware or electrical failure.