Date: December 1, 2009

Installations Affected: D10/D100 Series EFIS and EMS with the Keep Alive feature connected to the aircraft electrical power. SkyView is not affected by this bulletin.

Firmware Versions Affected: All firmware versions.

Time of Compliance: At any time.

Problem Description: Dynon has found that some D10/D100 Series EFIS and EMS can have problems booting up with the Keep Alive line connected. On EMS products, the Keep Alive line is used only to keep the clock running.

On EFIS products, the Keep Alive line is only used to keep the clock running if an internal battery is not installed. If the internal battery is installed, the Keep Alive recharges the internal battery even when master power is off (at the expense of pulling power from the aircraft battery). All other settings are stored in non-volatile storage.

Method of Compliance:

1. Disconnect the D10/D100 Series EFIS and/or EMS Keep Alive line from the aircraft power.
2. We also suggest you download and install the latest version of firmware, and connect a GPS output to your EFIS to keep the clock synchronized.