J.P. Instruments EDM 740 Pilots Guide - Manual (Page 20)

Page 20 Engine Data Management
Section 2 - Operating Procedures
Built-in Diagnostics: Startup and During Flight
When your EDM is first turned on, the screen begins by showing the
unit model number and TSO category. Next, several display patterns are
presented allowing you to check for proper screen operation. During this
time, the EDM is conducting built-in-tests of certain components,
calibration and probes. Any newly installed options are found and
logged in at this time. If a probe problem is found, diagnostic indications
will be presented on the display. These vary depending on the parameter.
For CHT, EGT and TIT, a message appears in the Scanner® Information
Area. For example, if EGT#2 were open circuit, the message would read
‘OPEN
EGT 2 ’. For an inoperative horizontal linear gauge function, a
red ‘ X ’ is drawn through it and its digital value is dashed out. Probes
determined to be faulty during the power up checks are disabled from
the Scanner® automatic sequence. During flight, probes are periodically
checked for inconsistent or intermittent signals and are disabled if
deemed unusable in which case an appropriate message will appear.
EDM Modes
The EDM has three different operating modes: Automatic, Manual and
LeanFind. When you first turn on the power the EDM starts in the
Manual mode, but will enter the Automatic mode after a few minutes.
The Automatic mode provides you with engine monitoring information
for the majority of flight conditions. To adjust the mixture, use the
LeanFind mode. To display specific parameters, use the Manual mode.
In either Automatic or Manual modes, the cylinder bar graphs show a
graphic representation of EGT and CHT for each cylinder and TIT (if
present).
Automatic Mode
Just tap the LF button, then tap the STEP button. No other user
intervention is required to use this mode. The EDM will begin
displaying the parameter sequence at the programmed ‘RATE’ (see
“Personalizing” on page 45).