TM 1–1520–238–T–3
Change 5
18–1
CHAPTER 18
AUXILIARY POWER UNIT (APU) MULTIPLEX READ CODES
FAILURE SYMPTOM INDEX
Symptom
Refer to paragraph
APU DOES NOT RUN; DISPLAYS FD/LS APU NO–GO OVERTEMP . . . . . . . 18–1, 18–11
APU DOES NOT RUN; DISPLAYS FD/LS APU NO–GO
OVERCURRENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18–1
APU RUNS; DISPLAYS FD/LS APU NO–GO UNDERSPEED . . . . . . . . . . . . . . 18–1, 18–10
APU RUNS; DISPLAYS FD/LS APU NO–GO OVERSPEED . . . . . . . . . . . . . . . 18–1, 18–10
APU RUNS; PTO CLUTCH DOES NOT ENGAGE . . . . . . . . . . . . . . . . . . . . . . . . 18–1, 18–10
APU DOES NOT RUN; DISPLAYS FD/LS APU NO–GO LOW OIL
PRESSURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18–1
APU DOES NOT RUN; DISPLAYS FD/LS APU NO–GO IGNITION NOT OFF
18–12
APU DOES NOT RUN; DISPLAYS FD/LS APU NO–GO UNDERSPEED . . . . 18–1, 18–10
APU START SEQUENCE – DOES NOT BEGIN AND APU FAIL LIGHT ON
CAUTION/WARNING PANEL LIGHTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18–1, 18–10
Personnel Required:
(2)
References:
TM 1–1520–238–T–8
Equipment Conditions:
Ref
Condition
TM 1–1520–238–T–8
AUXILIARY POWER UNIT
– MAINTENANCE
OPERATIONAL CHECK in
progress
NOTE
All multiplex read code responses are read from right to
left.
Multiplex read codes must be used in conjunction with
applicable Maintenance Operational Check (MOC) in
progress.
Multiplex read codes are observed on the HOD (ADC) or
CDU (ADD).
