Safety Relays - Toro Greensmaster 3150 Service Manual

Safety Relays

Several safety relays are used on Greensmaster 3150
machines. The safety relays are identical, five (5) termi-
nal relays that are used for circuit control.
Safety Relay Function
The start safety relay ensures that the functional control
lever is in neutral before engine starting is allowed. The
start relay is located under the control panel on the left
side of the operator seat.
When energized, the kill relay provides a complete cir-
cuit to allow the starter solenoid to be energized. Also,
when de--energized, the kill relay provides a ground for
the engine magnetos which stops the engine. The kill
relay is located under the control panel on the left side
of the operator seat.
The charge circuit relay allows alternator output to reach
the machine electrical circuits as long as the engine is
running. The charge circuit relay is located under the op-
erator seat.
When energized, the lower relay allows current flow to
hydraulic solenoid coils S2 and S4 causing the cutting
units to lower. The lower relay is located under the con-
trol panel on the left side of the operator seat.
The joystick relay allows cutting unit operation when en-
ergized by the joystick lower switch. The joystick relay
is located under the control panel on the left side of the
operator seat.
The mow relay allows the reel engage solenoid coil
(S1R1) to be energized for cutting reel operation. The
mow relay is located under the control panel on the left
side of the operator seat.
When energized, the raise relay allows current flow to
hydraulic solenoid coils S2 and S3 causing the cutting
units to raise. The raise relay is located under the control
panel on the left side of the operator seat.
When in backlap, the backlap relay prevents the cutting
reels from being engaged during engine cranking. The
backlap relay is located near the functional control lever.
NOTE: Refer to Circuit Diagrams in Chapter 9 -- Fold-
out Drawings for additional relay operation information.
Relay Testing
1. Park machine on a level surface. Make sure the en-
gine and ignition switch are OFF.
2. Locate relay that is to be tested.
Electrical System
3. Disconnect wire harness connector from relay that is
to be tested. If desired, remove relay from machine for
testing.
NOTE: Use illustration in Figure 13 to identify relay ter-
minals.
4. Use a multimeter (ohms setting) to measure resist-
ance between the following relay terminals:
A. There should be continuity between terminals
87A and 30
B. There should not be continuity between terminals
87 and 30.
C. Resistance between terminals 86 and 85 (relay
coil) should be from 80 to 90 ohms.
5. Connect multimeter (ohms setting) leads to relay ter-
minals 30 and 87. Ground terminal 86 and apply +12
VDC to terminal 85. The relay should make and break
continuity between terminals 30 and 87 as 12 VDC is ap-
plied and removed from terminal 85.
6. Disconnect voltage from terminal 85 and multimeter
lead from terminal 87.
7. Connect multimeter (ohms setting) leads to relay ter-
minals 30 and 87A. Apply +12 VDC to terminal 85. The
relay should break and make continuity between termi-
nals 30 and 87A as 12 VDC is applied and removed from
terminal 85.
8. Disconnect ground, voltage and multimeter leads
from relay terminals.
9. Replace relay if testing determines that relay is
faulty.
10.When testing is complete, secure relay to machine
if it was removed. Connect wire harness connector to
relay.
Page 5 - - 14
86 87A 87
85 30
Figure 13
Greensmaster 3150