What is the green LED for on the D8112?
When the green LED flashes, the CPU is normal.
When the green LED is off or on steady, the CPU is seized.
To reset the CPU, try a disable restart, or power down the panel, and power back up.
If this does not work replace the panel.
Part numbers D8112, D8112E, D8112E1, D8112G, D8112G1, D8112G2, D8112A