TM 55-1510-215-MTF
TROUBLESHOOTING GUIDE H-FLIGHT CONTROLS
CONDITION
PROBABLE CAUSE
H1. Autopilot is inoperative in all modes.
a.
No power to equipment.
b.
Defective autopilot computer.
H2. Autopilot circuit breaker does not hold in.
a.
Computer shorted to ground.
H3. Pressing AP DISC/TRIM INTER switch on control wheel
does not disengage autopilot.
a.
Defective AP DISC/TRIM INTER switch.
H4. ALT switch does not hold on.
a.
Defective pilot's encoding altimeter.
b.
Defective aircraft wiring.
H5. NAV switch does not hold on.
a.
Defective pilot's HSI.
b.
Autopilot not receiving selected navigation input signal.
H6. Autopilot does not hold heading.
a.
Heading selector not engaged.
b.
Defective mode controller.
c.
Defective computer.
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