Component Testing; Ignition Switch - Toro GroundsmasterR 4300-D Service Manual

Component Testing

For accurate resistance and/or continuity checks, elec-
trically disconnect the component being tested from the
circuit (e.g. unplug the ignition switch connector before
doing a continuity check of the switch).
NOTE: Electrical troubleshooting of any 12 volt power
connection can be performed through voltage drop tests
without disconnecting the component.
NOTE: Use the Diagnostic Display (see Special Tools
in this chapter) to test TEC controller inputs and outputs
before further troubleshooting of an electrical problem
on your Groundsmaster.

Ignition Switch

The ignition (key) switch has three positions (OFF, RUN
and START). The switch is mounted on the control con-
sole.
Testing
1. Before disconnecting the ignition switch for testing,
the switch and its circuit wiring should be tested as a
TEC controller input with the Diagnostic Display (see
Diagnostic Display in the Troubleshooting section of this
chapter). If the Diagnostic Display verifies that ignition
switch and circuit wiring are functioning correctly, no fur-
ther switch testing is necessary. If, however, the Diag-
nostic Display determines that ignition switch and circuit
wiring are not functioning correctly, proceed with test
procedure.
2. Remove outside control arm cover to gain access to
ignition switch (see Control Arm Disassembly in the Ser-
vice and Repairs section of Chapter 6 -- Chassis). Dis-
connect wire harness electrical connector from the
switch.
3. With the use of a multimeter (ohms setting), the
switch functions may be tested to determine whether
continuity exists between the various terminals for each
switch position. The ignition switch terminals are
marked as shown in Figure 18. The circuitry of this
switch is shown in the chart below. Verify continuity be-
tween switch terminals.
POSITION
OFF
RUN
START
4. Replace ignition switch if necessary.
Electrical System
CIRCUIT
NONE
B + C + F, D + E
A + B + C
NOTE: For engine component testing information, see
the Kubota Workshop Manual, Diesel Engine, 05--E3B
Series at the end of Chapter 3 -- Kubota Diesel Engine.
When testing electrical components for continu-
ity with a multimeter (ohms setting), make sure
that power to the circuit has been disconnected.
5. If switch tests correctly and circuit problem still ex-
ists, check wire harness (see Electrical Schematic and
Circuit Drawings in Chapter 8 -- Foldout Drawings).
6. Connect wire harness electrical connector to the
ignition switch.
7. Install control arm cover to machine (see Control
Arm Assembly in the Service and Repairs section of
Chapter 6 -- Chassis).
RUN
o
45
OFF
FRONT VIEW
Page 5 - - 22
CAUTION
o
45
START
A
B
C
REAR VIEW
Figure 18
Groundsmaster 4300--D
F
E
D