% Power going on & off

[Bob_B]

I recently strated flying with a new engine & I really like the % Power indicator my D-120 which helps me keep the power between 70-75% during engine break-in. However, yesterday while flying along at cruise speed 75% power, the indicator stopped working & went to dashed lines. I tried turning the unit OFF & back ON again, but was still not working. Several minutes later, the % Power indicator came back alive. Any ideas what is happening?

 

[dynonsupport]

% power requires:

RPM
MAP
OAT
Altitude

RPM and MAP are local to the EMS, so they're hard to lose.

OAT might be a local sensor to the EMS, or it might be on an EFIS.

Altitude my come from an EFIS, or a GPS.

If it happens again, I'd first make sure you are getting altitude, which may mean you need to check that your GPS has a good lock on the signal. If you have an EFIS, then the only thing you need is that the EFIS be on.

If everything is operating properly, it might be a wiring issue with an intermittent connection.