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
The information disclosed herein is proprietary to MD Helicopters, Inc.
Neither this document nor any part hereof may be reproduced or transferred to
other documents or used or disclosed to others for manufacturing or any other
purpose except as specifically authorized in writing by MD Helicopters, Inc.
Copyright
©
1999 − 2016 by MD Helicopters, Inc.
Table 101. Caution and Warning Lights Indicating System Troubleshooting (Cont.)
Symptom Corrective Action Probable Trouble
Light indicator does not light
with fault input signal applied
or when PRESS − TO − TEST
switch is pressed
Indicator lamp filaments open Replace lamps.
Defective component in dimming unit Replace defective component in
dimming unit, or replace dimming unit.
Defective switch in indicator Replace indicator.
Lighted indicator without a
fault signal applied
Defective component in dimming unit Replace defective component in
dimming unit, or replace dimming unit.
All caution and warning
indicator lights illuminate
except BATT 140/160, ENG
OUT, START PUMP and
PRESS − TO − TEST
Defective PRESS − TO − TEST switch
(S2)
Replace defective switch XDS21
Defective (shorted) diode(s) on
terminal board TB505 − 1/2
Replace terminal board module or use
spare module diodes
Short − circuit condition from Dimmer
P12 − B to ground
Inspect connections and wire
insulation; repair as necessary
Caution and warning indicator
lights illuminate (START
PUMP, ENG OUT and BATT
140/160)
Defective PRESS − TO − TEST switch
(S1)
Replace defective switch XDS21
Defective (shorted) diode(s) on
terminal board TB505 − 3/4
Replace terminal board module or use
spare module diode
NOTE:
If FUEL LOW caution indicator glows dimly when known fuel quantity exceeds 35/70 pounds (as applica-
ble), ensure that modification to fuel quantity sender has been performed (Ref. Fuel Quantity Sender Modifica-
tion to Prevent FUEL LOW Caution Light Activation), before replacing dimming unit or component(s) of dim-
ming unit.
Fuel filter caution light
illuminated
Fuel filter clogged (Ref. Sec. 05 − 40, Special
Inspections.)
Fuel filter pressure switch or wiring
defective
(Ref. Sec. 05 − 40, Special Inspections.
Warning Light Indicators
No ENG OUT indication from
either light indicator or audible
warning horn with engine out
fault input signal applied (or
low main rotor speed fault
input signal applied)
Disconnected or defective wiring to
EPO warning control unit
Reconnect or repair electrical wiring.
Defective sensing circuit in EPO
warning control unit
Replace EPO warning control unit.
Defective ENG OUT frequency sensor
or flasher circuit in EPO warning
control unit
Replace EPO warning control unit.
No ENG OUT warning light
indication with engine out fault
input signal applied; sound
from audible warning horn
present (or low main rotor
speed fault input signal
applied)
Indicator lamp filaments open Replace lamps.
Defective diode in dimming unit Replace or repair dimming unit.
Defective ENG OUT flasher in EPO warning control unit
Replace EPO warning control unit.