Toro 315-8 User Manual page 162

GLOSSARY
To shut the engine down if the operator gets off the
seat while the engine is running with the PTO engaged
or the brake released.
The seat switch consists of a pair of normally closed
contacts which open when the operator is on the seat
(Figure 23). One contact is connected in series to the
magneto through the brake switch. If the operator
vacates the seat while the engine is running, and the
brake released, the contacts close and the magneto is
grounded, stopping the engine.
The other contact is connected in series to the
magneto through the PTO switch. If the operator gets
off the seat with the PTO engaged and the brake
applied, the contacts close, connecting the magneto to
ground, stopping the engine.
1. Disconnect the switch from the wiring harness.
2. With a multimeter, check for continuity between
the switch terminals and ground. There should be
continuity.
3. Recheck for continuity with someone in the seat.
There should not be continuity.
The PTO switch is used to engage the electric clutch
(Figure 24).
tseatsw
It is also part of the safety circuit:
1. Prevents the engine from cranking with the key
switch in the start position when the PTO switch is
on.
2. It is part of the circuit that prevents the electric PTO
clutch from re-engaging after moving the shift lever
in and out of reverse without activating the reverse
caution mode.
3. It is part of the circuit that prevents the electric PTO
clutch from re-engaging if the operator gets off and
back on the seat.
The PTO switch uses three sets of contacts:
(Figure 25)
1. A – Com (normally closed)
Wired in series between the brake switch and start
solenoid. Preventing power from reaching the
starter solenoid when the PTO switch is on.
2. B – Com (normally open)
Connected in series between the relay coil and
the normally open relay contact. Once the relay is
energized these contacts provide a ground path to
the relay coil preventing it from de-energizing until
the PTO is switched off.
3. C – Com (normally open)
Connected in series between the A1 terminal of
tseatsw