J.P. Instruments EDM 930 Primary Primary Installation Manual - Manual (Page 39)

FAA Approved Installation Manual for the Report No 908
EDM-900 and EDM-930 Page 39 of 50 Rev J
Primary Engine Data Management System Date 5-24-2014
40. 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.
RED ‘X’ DRAWN THROUGH
ALL GAUGES FOR AN
ENGINE DAU failure or DAU communications error. Check power to DAU and wiring
harness connections.
CAL ERR Calibration error. Return unit to factory.
DSP XXX Internal communication error. Return unit to factory.
COMM ERR Internal communication error. Return unit to factory.
NO I 5 MV Calibration error. Return unit to factory.