Echo shindaiwa DCS-1600 Service Manual page 35

DCS-1600
5-1 Inspecting power switch and variable speed switch (Continued)
Terminal position
1 2 3 4
SWITCH AND TRIGGER
[Inspecting variable speed switch]
5. Inspect variable speed switch (B) as follows. If
the switch (B) is not as follows, replace with new
one.
B
(1) Inspection of short circuit
Connect one probe of multimeter to terminal "1"
of variable speed switch (B). Connect the other
probe to terminal "3". Multimeter should show
that the resistance value is between 70 kΩ and
130 kΩ.
(2) Inspection of electrical contact
Connect one probe of multimeter to terminal "1"
of variable speed switch (B). Connect the other
probe to terminal "4" .
When pressing variable speed switch (B),
multimeter should show that the circuit has
continuity. (Electrical current can flow between
terminal "1" and "4".)
When not pressing variable speed switch (B),
multimeter should indicate infinite resistance.
(Electrical current can not flow between termi-
nal "1" and "4".)
(3) Inspection of variable resistance part
Connect one probe of multimeter to terminal "1"
of variable speed switch (B). Connect the other
probe to terminal "2" .
When pressing variable speed switch (B) to the
end, multimeter should show that the resistance
value is 100 Ω or less.
When not pressing variable speed switch (B),
multimeter should show that the resistance
value is between 70 kΩ and 130 kΩ.
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