Raymarine autopilot ST4000+, Service Manual

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Chapter 4. Tiller Drive Actuator
Autopilots Service Manual 83115-1 21
Chapter 4. Tiller Drive Actuator
4.1 Tiller Drive Actuator test
Carry out the passive and active tests detailed in Figure 11. Tiller Drive Actuator
test flowchart.
D2394-1
Fuse/CB
12A
1
2 3
Blue Brown
Actuator deck plug
PSU
12V 15A
Switch
Blue
Brown
Figure 10. Tiller Drive Actuator test connections
Change damaged
components
Check gears,
thrust rod,
actuator body,
motor
Start
No
Yes
Visually inspect unit
Extend and retract
thrust arm by hand
No
Yes
OK
OK
Check resistance across
motor connector pins 2 and 3
is approximately 1 to 2 ohms
Change
as necessary
No
Yes
Check wiring
and connector
OK
Check motor
Change as
necessary
OK
Switch on,
check thrust rod moves and
current less than 2.5A
Connect power supply
as in Figure 10.
OK
No
Yes
Change
as necessary
Switch on.
Check thrust rod moves
in opposite direction
to that of first test and
current less than 2.5A
No
Yes
OK
Actuator OK.
End of test
D3728-1
No
Yes
Check gears,
thrust rod,
actuator body,
motor
Check gears,
thrust rod,
actuator body,
motor
Change
as necessary
Switch off.
Reverse connections to PSU
Figure 11. Tiller Drive Actuator test flowchart