Troubleshooting & Maintenance Flashcards
7 cards from real CPI practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Troubleshooting & Maintenance flashcards as text
A display installation shows intermittent flickering only at certain brightness levels. What is the most likely cause?
Answer: PWM dimming interference with the panel's backlight frequency
PWM (Pulse Width Modulation) dimming can cause flickering when the display's backlight frequency conflicts with the PWM cycle at specific brightness levels.
During a post-installation inspection, an installer notices condensation forming inside a sealed outdoor enclosure. What is the best corrective action?
Answer: Install a desiccant pack or membrane vent to manage humidity
A desiccant pack absorbs moisture while a membrane vent allows pressure equalization without letting liquid water in, preventing condensation buildup.
A newly installed digital signage player boots but displays a 'No Signal' message on the screen. What should be checked first?
Answer: The input source selection on the display
The display must be set to the correct input source (e.g., HDMI 1, DisplayPort) matching where the signal cable is connected to the player.
An audio system produces a 60 Hz hum after installation. Which condition is most likely responsible?
Answer: A ground loop between interconnected components
A 60 Hz hum is a classic symptom of a ground loop, which occurs when two or more components in the audio chain share different ground potentials.
What preventive maintenance step is most important for cooling fans in an AV rack installation?
Answer: Cleaning dust filters and inspecting fan blades on a regular schedule
Dust accumulation restricts airflow and can cause fans to fail, so regular cleaning and inspection are the most critical preventive maintenance steps.
A touch screen panel is registering incorrect touch positions after being moved to a new location. What is the most likely solution?
Answer: Recalibrate the touch screen through the display's settings menu
Touch screens can require recalibration when moved or after software updates to realign the touch input coordinates with the display image.
When troubleshooting a digital signage network, a technician finds that some players can communicate with the server but others cannot. What is the first step to isolate the problem?
Answer: Check IP address assignments and verify there are no conflicts or misconfigured devices
IP address conflicts or misconfiguration are a common cause of partial network communication failures and should be verified before more invasive steps.