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MAINTENANCE PANEL
The APU Maintenance Panel is installed in
the tailcone (Figure 6-10). The panel incor-
porates controls, indicators and interface ca-
p a b i l i t y f o r o p e r a t i o n o f t h e A P U f o r
maintenance purposes. The cockpit APU
MASTER switch must be ON to enable this
panel. Panel indications include:
APU FAIL/FAULT:
Indicator is an amber col-
ored LED that is illuminated by the ECU to in-
d i c a t e t h a t a f a u l t h a s b e e n d e t e c t e d
(maintenance, start inhibit or protective shut-
down).
APU OIL LEVEL:
Indication consists of two
amber lamps driven by the oil level switch to
provide an indication of oil level.
1. The “ADD” annunciator illuminates
at approximately 10 ounces (300 cc)
b e l ow f u l l . T h e A i r p l a n e F l i g h t
M a n u a l ( A F M ) , O i l S e r v i c i n g
Addendum indicates no action is re-
quired at this point.
2. The “LOW” annunciator illuminates
at approximately 18.5 ounces (550
cc) below full. The Oil Servicing
Addendum indicates that action is re-
quired. At the time the LOW annun-
ciator is illuminated the operator has
five (5) hours of operation until oil
must be added to the APU gearbox.
3. Activation of the momentary OIL
TEST switch must only be accom-
plished when the APU is not running.
E M E R G E N C Y S H U T D OW N :
Removes
electrical power from the ECU, which causes
the APU to shutdown. On the next ECU power
up a “Loss of DC Power” fault is logged.
RS232 PORT:
Provides the interface be-
tween the ECU and the PC Monitor System
used by maintenance personnel.
OIL SERVICING
Servicing the onboard APU oil system consists
of periodic oil changes and normal between-
oil-change servicing (adding oil).
Refer to AFM Supplement for information.
6-11
FOR TRAINING PURPOSES ONLY
L E A R J E T 4 5
P I L O T T R A I N I N G M A N U A L
FlightSafety
international
FSM
CABLE
PORT
APU
FAIL/FAULT
LIGHT
APU EMERGENCY
SHUTDOWN SWITCH
APU ADD
OIL LIGHT
APU OIL
LOW LIGHT
APU OIL
TEST SWITCH
Figure 6-10. APU Maintenance Panel