190-01717-B1
G500/G600 TXi Part 23 AML STC Maintenance Manual
Rev. 1
Page 4-34
Figure 4-25 EIS Gauge Troubleshooting
EIS Gauges
If fault still exists,
contact Garmin.
Unstable
RPM
Resistor failure
OR
Poor connection
OR
Interference
Starting vibrator is
installed. Normal
operation with P-
Lead RPM input.
Cause
Disconnect P-Lead
signal wires at
both ends. Verify
wire is more than
400KOhms.
Replace wire and
parallel resistors if
less than
400KOhms.
Verify wiring and
connections
Route signal wires
away from spark
plug leads and
power wires
Disconnect P-Lead
signal wire at both
ends of suspect mag.
Verify wire is more
than 400 KOhms.
Replace wire and
parallel resistors if less
than 400KOhms.
Verify wiring and
connections
Corrective
Action
Loss of RPM
during mag.
check
Cause
Resistor failure
OR
Poor connection
Corrective
Action
RPM is
erratic during
engine start/
cranking
Replace fuel probe
Fuel quantity
gauge
inaccurate
Corrective
Action
Poor connection
OR
Air/contamination in the
sensor
OR
Incorrect sensor config.
OR
Interference
Fuel flow
indication
unstable
Cause
Corrective
Action
Fuel flow requires
calibration
Calibrate fuel flow.
Limited to 15% in
GDU Normal
Mode. More
adjustment will
require a different
K-Factor.
Fuel totalizer
inaccurate
Cause
Corrective
Action
Verify wiring and
connections
Purge fuel lines of
air, verify sensor
orientation, clean
the sensor.
Configure sensor with
‘Hi’ filtering option
Cause
Poor connection
OR
Fuel probe
malfunction
OR
Probe out of
calibration
Cause
Verify wiring and
connections
None
Corrective
Action
Route wires away
from spark plug leads
and power wires,
install EMI shield
Replace fuel flow
transducer
Replace fuel flow
transducer
Recalibrate fuel
tank probes
Pressure line drain
plugged/line blocked
OR
Sensor failure
Verify manifold
pressure line vent
(if installed) is
clear.
Verify fuel is not
trapped in the
manifold pressure
line.
Manifold
pressure
unstable
Cause
Corrective
Action
Replace manifold
pressure sensor
Pressure line
blocked
OR
Sensor out of cal.
OR
Sensor failure
Verify manifold
pressure line is
clear.
Manifold
pressure
inaccurate
Cause
Corrective
Action
Recalibrate
manifold pressure
sensor (brass
sensor only)
Replace manifold
pressure sensor