Stihl MS 661 C-M

64 MS 661, MS 661 C-M
8.3.5 Checking Detection of
Start Conditions
– Carry out preparations, b 8.3.1
– Test screw and plug connections,
b 8.3.3
: Set the Master Control lever (1)
to }, the lever (2) must operate
the microswitch (arrow) in this
process – audible click.
: Remove the connector (1) from
the solenoid valve (2) – do not
tug wires to remove the
connector.
1166RA234 TG
2
1
1166RA236 TG
2
1
: Lift locking tab (arrow) and pull
off the flag terminal (1).
– Check the flag terminal,
disassemble and clean if
necessary, b 7.10
– Set the Master Control lever to
}.
– Connect test cable, b 8.3.2
– Connect M-Tronic test cable to
multimeter.
: Connect black plug (1) to "com" /
"ground" socket and red plug (2)
to "Volt" / "Ohm" socket.
– Set multimeter to "diode test".
: Test diode on switch
unit (3) (microswitch) – follow
instructions supplied with
multimeter.
1166RA237 TG
1
3
2410RA238 TG
2
1
If the switch unit (microswitch) is in
order and the Master Control lever
is on }, the following values are
obtained:
– Measurement in forward
direction, specified value: 0,3 V
to 0.7 V
– Set the Master Control lever to F
– Measurement in reverse
direction,
specified value: 1,2 V to infinity
– observe display, e.g. (O.L.)
or (1.)
– If specified values are not
obtained, replace the switch unit
and repeat the test procedure,
b 8.5
– If the specified values are still not
obtained, replace the wiring
harness, it may be possible to re-
use the existing switch unit,
b 7.10
– Reassemble all other parts in the
reverse sequence.