Can the Master Caution illuminate without the System Annunciator Panel on the 737NG?
If everything is working as designed then the Master Caution is always accompanied by one of the 12 annunciator lights (or more than 1, depending on the situation).
If things aren't working as designed, then what you'll see depends on the nature of the malfunction. If it's as simple as a burned-out bulb in the annunciator panel, then you could get the Master Caution without an accompanying light. That's usually followed by a disgruntled &quot;oh, great&quot; followed by heads swiveling around to find what individual amber light is illuminated. And/or pressing the Recall function (see what fails to light up, or comes on now), and/or using the Lights Test switch.