John Deere 318 - Manual (Page 335)

4d
PTO Clutch Test
Separate PTO clutch
connector at right-hand
side of engine.
NOTE: Machines
(S.N. —475000)
shown. Later machines
use a 2-pin connector.
M36626 -UN-25JAN90
Connect a jumper wire
to battery positive (+)
terminal and jump to
dark blue clutch lead
(A).
For machines (S.N.
475001— ), also
connect a jumper wire
from the black PTO
clutch lead to ground.
LISTEN: Clutch should
“click” when engaged.
CLUTCH ENGAGES:
For machines (S.N.
475001— ), check
continuity between
ground and the black
wire contact at main
harness side of PTO
clutch connector. If no
continuity, repair or
replace harness ground
wire, then GO TO
Å
,
Group 05.
CLUTCH DOES NOT
ENGAGE: Check for
good ground. If ground
OK, repair clutch: GO
TO Section 40.
4e
Seat Switch
Circuit Test for
PTO or Ignition
Circuits.
NOTE: Jumper wire (A)
not required for this
test.
Disconnect seat switch
connector.
M36627 -UN-25JAN90
Turn key switch to the
RUN position.
Check for voltage at
harness side of
connector.
VOLTAGE: GO TO
4f
NO VOLTAGE: GO TO
4h
4f
Seat Switch Test
Key switch OFF.
Disconnect seat switch
connector.
Connect ohmmeter or
continuity tester across
switch side of
connector.
There should NOT be
continuity.
Press down on center
of seat.
There should be
continuity.
Connect switch after
testing.
SEAT SWITCH OK:
GO TO
4g
SEAT SWITCH NOT
OK: Replace switch,
then GO TO
Ú
and
Ü
,
Group 05.
4g
Seat Switch
Circuit Test at TDC
2-Pin Connector
Install jumper wire
across seat switch
connector or have
someone sit on seat.
M37289 -UN-25JAN90
Turn key switch to RUN
position.
Check for voltage at
pink wire at TDC 2-pin
connector (A).
VOLTAGE: Circuit OK,
GO TO
4j
NO VOLTAGE: Replace
pink wire between seat
switch and TDC 2-pin
connector.
4h
2-Amp or 3-Amp
Power Circuit Test
at TDC 8-Pin
Connector
NOTE: For machines:
316 (S.N. 475001— )
318 (S.N. 475001— )
420 (S.N. 595881— ),
a 3-amp fuse is used.
Turn key switch to
RUN position.
M55133 -UN-11DEC89
Check for voltage at
red and pink leads (A)
at TDC 8-pin connector. VOLTAGE: Replace
pink wire between seat
switch and TDC 8-pin
connector.
NO VOLTAGE: GO TO
4i
MX,159024025,60-19-16MAY95
MX,159024025,61-19-16MAY95
MX,159024025,62-19-16MAY95
MX,159024025,63-19-16MAY95
MX,159024025,64-19-16MAY95
Electrical System Diagnosis/PTO Clutch and Lamp Tests
TM1590 (17MAY95)
240-20-23
316, 318 & 420 Lawn and Garden Tractors
020895
240
20
23