What trouble conditions cause the Aegis 2.0 to display a PR1 trouble code, and how do I clear it?

I couldn't find a "PR1" trouble code in our manuals for the Kidde AEGIS 2.0. The panel uses 3-digit numeric diagnostic codes (000-038) to identify specific faults (Page 69, 75) [1].

To view the actual diagnostic codes, press and hold the Signal Silence control switch for five seconds; the codes will sequence on the digital display until the switch is released (Page 72) [1].

If you are seeing a "P" on the display, it may refer to a Pre-release state (buzzer pattern "P") or a Pseudo-Trouble such as code 035 (ARC #1 Outputs Disabled), which is cleared by pressing the Output Disable switch a second time (Page 69, 76) [1].