MD Helicopters 369-500, Maintenance Instructions Manual

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CSP-HMI-3
MD Helicopters, Inc
.
MAINTENANCE MANUAL
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Revision 7
95-00-00
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Neither this document nor any part hereof may be reproduced or transferred to
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purpose except as specifically authorized in writing by MD Helicopters, Inc.
Copyright
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1999 − 2016 by MD Helicopters, Inc.
(5). Start refueling slowly. Note that FUEL
LOW caution light goes out shortly
after gauge passes 35 pounds position,
approximately 5.4 gallons (20.5 liters).
If light does not go out completely,
remove tank sending unit and bench
test (Ref. Sec. 28-00-00).
(6). Continue to fill cells to 200 pounds,
approximately 30-3/4 gallons (116.4
liters) of fuel.
(7). Check that gauge reading at 200
pounds is within scribed tolerance
marks on template.
(8). Continue to refuel until tanks are full.
Check that indication is within toler­
ance marks.
(9). Remove electrical power and stop
refueling operations. If fuel quantity
indications were not within tolerances,
test tank sending unit (Ref. Sec.
28-00-00).
3. Caution/Warning System Operational
Check
An operational check of caution and warning
lights indicating system must be performed
after maintenance on caution and warning
lights, EPO warning equipment, Autronics
Indicator Lights Dimmer Assembly or disable
switch S199.
Special Tools
(Ref. Section 91 − 00 − 00)
Item Nomenclature
N/A Jumper lead
NOTE:
Although procedure below reveals func­
tional state of only three of the fault input
circuits, it also determines whether or not
components common to all circuits function
correctly. A check of the other fault input cir­
cuits can be made in the same way, when
necessary, by bridging the applicable
switching device or sender.
(1). Turn on electrical power.
(2). Check that PANEL lights and ENG
OUT circuit breakers are in (reset) and
that panel lights dimmer control is at
OFF (fully counterclockwise).
NOTE:
Fault input for indications in next step
is supplied when engine is not operating.
(3). Check that red warning light (indicat­
ing engine out) flashes, and that main
rotor transmission oil pressure warning
light is illuminated.
(4). Using jumper lead, ground terminal
stud of tail rotor transmission chip
detector (Ref. Sec. 63-25-10) to produce
a fault input. Check that tail rotor
transmission chips light is illuminated.
(5). Check that panel lights dimmer control
can control panel instrument and light
illumination.
(6). Turn electrical power off.
4. Autronics Indicator Lights Dimmer
Assembly Test
(Ref. Figure 601)
Special Tools
(Ref. Section 91 − 00 − 00)
Item Nomenclature
N/A Multimeter
N/A Power supply, +28 Vdc
(1). Test diodes, using an ohmmeter at
electrical connector pins. Check for low
forward resistance with positive lead
applied to the anode and negative lead
applied to the cathode. Read very high
back resistance when leads are re­
versed.
(2). Test switching regulator by applying
+28 Vdc at electrical connector pin V
and ground at pin W. Check output at
pin d for 2.5 Vdc minimum. Apply +28
Vdc at pin X and check output at pin d
for 26 Vdc minimum.
(3). Replace faulty internal components, or
replace unit if necessary.