MD Helicopters 369-500, Maintenance Instructions Manual

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CSP-HMI-3
MD Helicopters, Inc
.
MAINTENANCE MANUAL
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[ HMI − 3 Book TOC ]
[ Chapter 95 TOC ]
95-00-00
Page 101
Revision 12
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.
INSTRUMENTS
FAULT ISOLATION
1. Caution/Warning System Troubleshooting
When troubleshooting, perform an operational
check (Ref. Caution/Warning System Opera­
tional Check) as necessary.
Troubleshoot the caution and warning lights
indicating system, using data below (Ref.
Table 101). To determine the functional unit
associated with each light indicator, use Table
101. To assist in isolating trouble to a defective
unit and component, use Table 102.
2. Instrument Troubleshooting
(Ref. Table 103, Figure 101 and Figure 102)
Comply with electrical safe­
ty precautions (Ref. Sec.
96-00-00) when troubleshooting or re­
placing instruments.
Table 101. Caution and Warning Lights Indicating System Troubleshooting
Symptom Probable Trouble Corrective Action
NOTE:
Unless specified otherwise, troubleshooting is accomplished with Autronics EPO Warning Control Unit
(Ref. Sec. 95 − 30 − 00) and Autronics Indicator Lights Dimmer Assembly installed, electrical power on, WARN-
ING and PANEL LAMPS and ENG OUT circuit breakers in (reset), and panel lights dimming control set at BRT.
Caution and Warning Light Indicators
Indicator light erratic or
inoperative when checked by
PRESS − TO − TEST switch
Circuit wiring loose, shorted, open or
incorrectly connected
Inspect electrical connections, repair
as necessary.
Indicator defective Replace defective lamp or indicator
socket.
One or more light indicators,
but not all, do not light when
PRESS − TO − TEST switch is
pressed
Indicator lamp filaments open Replace lamps.
Open diode in dimming unit Replace diode associated with
unlighted indicator or replace dimming
unit.
Indicator light on; associated
system functioning normally
Short − circuit in light circuit Check light circuit wiring; repair as
necessary.
Sensor/sender unit defective Replace sensor/sender.
Abnormal light indication(s)
peculiar only to caution light
indicator(s)
Refer to corrective action column Refer to caution light indicators
information below.
Abnormal light indication(s)
common to both caution and
warning light indicator(s)
Refer to corrective action column Refer to warning light indicators
information below.
Abnormal light indication(s)
peculiar only to warning light
indicator(s) and/or audible
warning horn
Refer to corrective action column Refer to warning light indicators
information below.
WARNING