J.P. Instruments EDM-350 User Manual

Approved Installation Manual for the Experimental Report No 104
EDM-350 Page 38 of 46 Rev A
Engine Data Management System Date 7-10-2021
37. Trouble Shooting
Diagnostic Testing on Startup and During Flight
When your EDM is first turned on it tests internal components, calibration and integrity of the probes.
During flight, probes are constantly checked for inconsistent or intermittent signals.
Problem
Situation
Correction
A MISSING COLUMN IN THE
DISPLAY UPON START UP
Diagnostic routine has found an open line
or probe with no connection.
Replace the EGT or CHT probe shown
in the error message
A MISSING COLUMN IN THE
DISPLAY DURING FLIGHT
A reading that is jumping around or
incorrect
The probe is removed from the line up
Replace the EGT or CHT probe shown
in the error message on the next flight.
DISPLAY FREEZES OR MAY
BE INCORRECT
A power transient could cause the
processors to malfunction
Recycle the power to the EDM
LEANFIND FINDS A “PEAK”
TOO SOON
Failure to pre-lean before performing
LeanFind or stopping while leaning.
Leaning too slowly
Continue to lean without stopping
Lean more rapidly
PEAK NOT FOUND DURING
LEANFIND
Lean Find not activated or stopping while
leaning
Lean at the speed of approximately
10°F per second
OFF-SCALE EGT COLUMNS,
TOO HIGH OR LOW
Off-scale EGT column readings. EDM in
the Normalize view (blue EGT scales).
Return to Standard mode by holding
the LF button.
FIRST CYLINDER TO PEAK
IS NOT THE HOTTEST
The first to cylinder peak is not necessarily
the hottest
This is normal.
EGTS RISE DURING SINGLE
MAGNETO CHECK
Incomplete combustion persisting longer
This is normal.
EGTS NOT UNIFORM
DURING LOW POWER
OPERATION
Fuel and air distribution is not optimal at
low power settings
This is normal.
0.0 GPH
Zero’s indicate Fuel flow is too low to
register
This is normal.
--- GPH
Dashes indicate No fuel flow transducer
signals
Have the mechanic verify if it is the
sensor or wiring.
--- H.M
Dashes indicate No fuel flow transducer
signals
No GPS signal, check the wiring
OPEN PRB
Open probe.
Wiring to probe is open circuit. Check
wiring and crimps. Swap probes to
troubleshoot.
BAD-PRB
Bad probe.
Erratic reading. May be poor electrical
connection. Swap probes to
troubleshoot.
RED ‘X’ DRAWN THROUGH
A SINGLE GAUGE
Measurement out of range.
Have the mechanic verify if it is the
engine or the sensor. Replace as
necessary.

J.P. Instruments EDM-350 Specifications

General

Brand	J.P. Instruments
Model	EDM-350
Category	Avionics Display
Language	English