If you have upgraded LC1140 or LC2140 panels using the P3 Upgrade Kit so that they accept the same P3 video data signal as the LC Plus, we recommend that you update the panels with the latest LC Plus panel firmware available (version 1.0.5 as of July 2009).
You can download the latest LC Plus panel firmware -- together with a Service Note to help you set up a P3-100 System Controller to carry out the firmware update -- from the Software section of the LC Plus Series Support page here on www.martin.com