When installing the DFC90 into an approved aircraft, if you see the Entegra PFD Autopilot Message bar dashed out (see photo), you need to check the configuration of the AutoPilot in the PFD Maintenance Mode pages.

Ensure the PFD has MOD55 (mandatory requirement for the DFC90), otherwise the DFC90 cannot communicate with the PFD. 

The photo shows the PFD software is (possibly) not configured for DFC90. It is (more than likely) configured for Stec55x.

Those dashes at the top of the PFD are the invalid annunciator display for an Stec configuration.

The reason the DFC90 has an impact is the common pins between the DFC90 and an Stec. The DFC90 uses 3 serial lines and they connect to the same pins used for annunciator on an Stec. The RS232 data from the DFC90 is being transmitted to the PFD and the PFD is trying to interpret the data as the 3-wire clocked serial stream of an Stec55 annunciator instead of the DFC90 data.

Remember to always use the latest Installation Guides when installing the DFC90 with the Entegra PFD.