Dynon Skyview Powerup Problem

[mikeschumann]

About a month ago, I had a strange problem where the Dynon Skyview EFIS Display would not power up.  The display stayed totally black when I turned on the EFIS circuit breaker.

I initially suspected a power problem.  However all my other instruments worked properly.  My LXNav Variometer showed 12.6 V, so I knew I had good power to the circuit breaker panel.

We removed the Dynon Skyview Display and checked the voltage and ground on the 29 pin main connector.  Again both power pins showed 12.6V when the EFIS breaker was on.

After talking to Dynon, they issued an RMA for me to return the Skyview Display.  After they received it, it worked just fine on the bench.  They suspected that I had a wiring issue.  To double check, they sent me a re-manufactured exchange unit, which ended up having the same problem.

At this point, we removed the center instrument panel so we could get at the back of the circuit breakers to measure the voltage while the Skyview Display was installed.  Low and behold, when the EFIS breaker was pushed in the voltage accross the breaker varied between 2 to 12.6V.  What apparently was happening was the breaker was working fine without a load.  However with a load it was continuously trying to trip (you could hear a very faint humming from the breaker). 

We ended up replacing the breaker, which solved the problem.  Note:  The breaker was epoxied into the panel, and the two breaker leads were soldered to the bus bar and the wiring harness, so this took a little work (see attached photo).  The good news is that the wiring harness to the circuit breaker panel had a large round connector, so it was very easy to remove the center instrument panel from the aircraft to work on it.

One tip that would have made diagnosing the problem easier:  If you hold down the left most button on the Skyview display, it will power up using the backup battery even with no power from the EFIS breaker.  This will let you see the voltage being fed to the Skyview Display, so you can tell if you have a power problem without accessing the back of the circuit breaker panel.

As always, the Dynon folks were a tremendous help.  The quality of the workmanship of the avionics installation that was done by Sebastian was exceptional.

Hope this posting helps anyone else who runs into a similar problem.