User Manual

316, 318 AND 420 ELECTRICAL SCHEMATIC—SINGLE PTO
A1—TDC Module M2—Starter Motor: X5—Rear PTO Harness 3-Pin X17—Headlight Harness
A2—Ignition Module 316 (S.N. —362983) Connector Connector
(S.N. 420001— ) 318 (S.N. —364137) X6—Rear PTO Switch 2-Pin 1-Pin (S.N. —475000)
B1—Engine Oil Pressure 420 (S.N. —360009) Connector 2-Pin (S.N. 475001— )
Switch N1—Voltage X7—Rear PTO Switch 3-Pin X18—Tail Light Harness
C1—Condenser Regulator/Rectifier Connector Connector
(S.N. 420001— ) P1—Front PTO Indicator X8—Brake Switch 2-Pin 1-Pin (S.N. —475000)
E1—Spark Plug P3—Hour Meter Connector: 2-Pin (S.N. 475001— )
E2—Spark Plug P4—Battery Discharge 316 (S.N. 596121— ) X19—Engine Oil Pressure
E3—Ignition (Breaker) Points Indicator 318 (S.N. 600305— ) Switch 1-Pin Connector
(S.N. —420000) P5—Engine Oil Pressure 420 (S.N. 595881— ) X20—Hour Meter 1-Pin
E4—Left Headlight Indicator X9—Transmission Neutral Connector
E5—Middle Headlight S1—Key Switch Switch 1-Pin Connector X21—Hour Meter 1-Pin
E6—Right Headlight S2—Front PTO Switch X10—Transmission Neutral Connector (Ground)
E7—Left Tail Light S4—Brake Switch: Switch 1-Pin Connector X22—TDC Module 2-Pin
E8—Right Tail Light 316 (S.N. 596121— ) X11—Seat Switch 2-Pin Connector
F1—20-Amp Fuse 318 (S.N. 600305— ) Connector X23—TDC Module 8-Pin
F2—2-Amp Fuse: 420 (S.N. 595881— ) X12—Engine Harness 3-Pin Connector
316 (S.N. —475000) S5—Transmission Neutral Connector X24—Rear PTO Clutch 1-Pin
318 (S.N. —475000) Switch X13—Voltage Connector (Ground)
420 (S.N. —595880) S6—Seat Switch Regulator/Rectifier X25—Rear PTO Lamp 1-Pin
3-Amp Fuse: S7—Headlight Switch 1-Pin Connector (VDC Connector (Ground)
316 (S.N. 475001— ) T1—Ignition Coil Output) X26—Front PTO Clutch 2-Pin
318 (S.N. 475001— ) W1—Engine Ground X14—Voltage Connector
420 (S.N. 595881— ) (S.N. 475001— ) Regulator/Rectifier X27—Single Point Ground
F3—25-Amp Circuit Breaker X1—Key Switch 5-Pin 1-Pin Connector 1-Pin Connector:
G1—Battery Connector (Stator) 316 (S.N. 596121— )
G2—Stator Alternator X2—Key Switch 1-Pin X15—Voltage 318 (S.N. 600305— )
K1—Starter Solenoid: Connector Regulator/Rectifier 420 (S.N. 595881— )
316 (S.N. —362983) X3—Front PTO Switch 2-Pin 1-Pin Connector Y1—Front PTO Clutch
318 (S.N. —364137) Connector (Stator)
420 (S.N. —360009) X4—Front PTO Switch 3-Pin X16—Headlight Switch 2-Pin
M1—Starter Motor: Connector Connector
316 (S.N. 362984— )
318 (S.N. 364138— )
420 (S.N. 360010— )
Legend For Electrical Schematic
NOTE:
Wire colors are the same for all machines.
Wire numbers indicated on schematic are for
machines (S.N. 475001— ).
1. For 316 (S.N. —596120), 318 (S.N.
—600304) and 420 (S.N. —595880)
machines, brake switch (S4) is not used.
Purple wire “710” connects transmission
neutral switch directly to terminal “S2” of key
switch.
2. For machines (S.N. —475000), a light
green wire is used instead of the red “210”
wire used on later machines. The green wire
connects to terminal “B” of key switch (S1),
not to circuit breaker (F3) as does the red
“210” wire.
NOTE:
3. The electrical schematic shows ground
circuits for machines (S.N. 475001— ). For
these machines, all component grounds
terminate (spliced) inside the main harness
with one wire connecting to a single ground
point at the engine.
For machines (S.N. —475000), the (blk)
ground wires for the PTO lamps, hour meter,
and TDC module (2-pin connector) terminate
at the right pedestal panel. Exterior
components, such as the PTO clutches and
head and tail lights use the tractor frame for
ground.
MX,159024015,1 -19-16MAY95
Electrical Schematics
TM1590 (17MAY95) 240-10-2 316, 318 & 420 Lawn and Garden Tractors
020895
240
10
2