Stihl MS 650

101MS 650, MS 660
14.5.2 Test Connections and Test Values
– The pin and socket connections
of the wires in the rear handle
must be disconnected to test the
individual components
separately.
1)
Pull out wire for this purpose
Component Ohmmeter connection
(use either test lead)
Resistance Ω If faulty
Lead 1 Lead 2 Spec. Actual Cause Remedy
Switch Switch
terminal
1)
Switch
housing
< 0.5 - Switch faulty Replace switch
Connector tags Connector
tags
Ground 0 > 1.0 Poor ground
connection
Replace ground
wire
Heating element in
rear handle
Connector
on wire
from rear
handle
heating
element
Connector
on wire
from rear
handle
heating
element
1.0 0.8...1.2 Heating element
OK
- Break in wire,
heating element
damaged
Install new heating
element or repair
insulation
0 Short circuit –
damaged insulation
Heating element in
front handle
Connector
on wire
from front
handle
heating
element
Ground 7.0 6.0...8.0 Heating element
OK
- Break in wire,
heating element
damaged
Install new front
handle
0 Short circuit –
damaged insulation
Repair
insulation
Generator Connector
on red
wire
Ground 0.5 0.3...1.0 Generator OK