Testing - Stihl MS 201 Manual

7.6 Short Circuit Wire
The ground and short circuit wires
are combined in a wiring harness.
If the spark plug, ignition lead and
spark plug boot are in order, check
the short circuit wire.
7.6.1

Testing

– Remove the fan housing, b 8.2
1
3
: Pull the short circuit wire (2) out
of the guide (arrow) and
disconnect the terminal (1).
: Connect the ohmmeter to
ground (3) and the short circuit
wire's terminal (1).
– Set the Master Control lever to
"STOP" or "0".
The resistance measured must be
about 0 Ω. If it is much higher, the
reason is a break and the wiring
harness has to be replaced, .
MS 201 b 7.6.2,
MS 201 T b 7.6.3.
– Set the Master Control lever to
"F".
The resistance measured must be
infinitely high. If not, replace the
wiring harness,
MS 201 b 7.6.2,
MS 201 T b 7.6.3.
48
Also perform a contact and
continuity test on the ground wire
between the connector sleeve and
the contact spring and between the
terminals and contact springs.
– If no fault can be found, check the
ignition system with the aid of the
troubleshooting chart, b 7.7
– Reassemble in the reverse
sequence.
7.6.2 Removing and Installing
(MS 201)
– Pull the boot off the spark plug.
– Remove the fan housing, b 8.2
2
2
3
: Pull the short circuit wire (1) out
of the guide (arrow).
: Disconnect terminals (2) and (3).
1
: Take out the screws (1) with
washers.
: Put the ignition module (2) to one
side.
– Remove the handle housing,
b 10.4
– Remove the lockout lever and
throttle trigger, b 10.2
– Remove the choke and throttle
rods, b 10.3.1
– Remove the switch shaft,
b 10.1.1
1
– Remove the contact spring,
b 7.6.5
2
1
: Take out the screw (1) and
remove the AV spring (2).
MS 201, MS 201 C, MS 201 T, MS 201 TC
1
2