When verifying the electrical system conditions, the controller pilot should be:

• A. Illuminated (power on)
• B. Dimmed
• C. Off
• D. Flashing

Answer: (A)

The main idea is that you need a clear indication that the control circuit is powered before you verify electrical conditions. The controller pilot light serves as a straightforward status indicator that the controller is energized. When it is illuminated, it confirms that the incoming power is present, the control circuitry is energized, and the system is ready to respond to test signals.

If the pilot were dim, it could point to reduced voltage, a weak lamp, or partial power—any of which means you can’t rely on the indicator to confirm normal operation. If it were off, there would be no power to the controller, so the verification would not reflect actual operating conditions. A flashing pilot often signals a fault or alarm condition, which would mask normal readiness and prompt additional checks before continuing.

So, keeping the controller pilot illuminated ensures you’re testing under proper, powered conditions and that the electrical system status is truly ready for the verification steps.