Toro Groundsmaster 3280-D Service Manual page 261

Testing the PTO Switch
Groundsmaster ® 3280-D/3320
05138SL Rev B
During the operation of the machine, if the PTO shuts down and
the console temperature warning light is illuminated because of
excessive engine coolant temperature, avoid shutting off the engine.
Under this condition, push the PTO knob down, slowly drive to a
safe flat area, move the throttle lever to the S
traction pedal, and set the parking brake. Allow the engine to be
idle for several minutes while it cools to a safe level, and check the
cooling system before returning the machine to service.
1. Park the machine on a level surface, lower the cutting deck, set the parking
brake, and shut off the engine.
2. Before you disconnect the PTO switch for testing, ensure that you test the
switch and its circuit wiring as a SCM input; refer to
(SCM) (page 6–3).
3. If the SCM verifies that the PTO switch and circuit wiring are functioning
correctly, no further switch testing is necessary.
4. If the SCM determines that the PTO switch and circuit wiring are not
functioning correctly, then test the PTO switch as follows:
A. Remove the 4 thumb screws (item 3 in
panel to the fuel tank.
B. Ensure that the key switch is in the O
harness connector from the PTO switch.
C. The PTO switch terminals are identified in
the PTO switch is shown in the
use of a multimeter (ohms setting), test the switch functions to determine
if the continuity exists between the various terminals for each switch
position. Check the continuity between the switch terminals.
Circuit Logic Table
Switch Position
O (D )
FF OWN
O (U )
N P
D. Replace the PTO switch if testing determines that the switch is damaged.
E. If the PTO switch testing is correct and a circuit problem still exists, check
the wire harness; refer to the Electrical Schematics and Wire Harness
Drawings/Diagrams in
F. After you complete the testing, connect the machine wire harness
connector to the PTO switch.
G. Secure the control panel to the machine with the 4 thumb screws.
IMPORTANT
Figure
FF
Circuit Logic Table (page
Closed Circuits
COM B + NC B
COM C + NC C
COM B + NO B
COM C + NO C
Appendix A (page
Page 6–33 Electrical System: Testing the Electrical Components
position, press the
LOW
Standard Control Module
133) that secure the control
position. Disconnect the wire
Figure 134 and the circuitry of
6–33). With the
Open Circuits
COM B + NO B
COM C + NO C
COM B + NC B
COM C + NC C
A–1).