Hydraulic Solenoid Valve Coil - Toro GroundsmasterR 4300-D Service Manual

Hydraulic Solenoid Valve Coil

The Groundsmaster 4300--D hydraulic system uses
several hydraulic solenoid valve coils for system control.
The deck control manifold includes two (2) solenoid
valves (Fig. 46) and the lift control manifold includes
three (3) solenoid valves (Fig. 47). When the solenoid
coils are energized, hydraulic valve shift occurs to con-
trol hydraulic flow. Testing of the coils can be done with
the coil installed on the hydraulic valve.
Testing
1. Before disconnecting solenoid valve coils, test the
solenoids and their circuit wiring as TEC controller out-
puts with the Diagnostic Display (see Diagnostic Display
in the Troubleshooting section of this chapter). If the
Diagnostic Display verifies that solenoid coils and circuit
wiring are functioning correctly, no further testing is nec-
essary.
2. If the Diagnostic Display determines that coils and
circuit wiring are not functioning correctly, park machine
on level surface, lower cutting decks, stop engine, apply
parking brake and remove key from ignition switch.
3. To gain access to deck control manifold (Fig. 46),
raise and prop the operator seat. Access to the lift con-
trol manifold (Fig. 47) can be obtained by removing the
operator floor plate.
4. Disconnect harness electrical connector from hy-
draulic solenoid valve coil that is to be tested (Fig. 46 or
47).
NOTE: Prior to taking small resistance readings with a
digital multimeter, short the meter test leads together.
The meter may display a small resistance value (usually
0.5 ohms or less). This resistance is due to the internal
resistance of the meter and test leads. Subtract this val-
ue from the measured value of the component you are
testing.
5. Using a multimeter (ohms setting), measure resis-
tance between the two connector terminals on the sole-
noid valve coil. The resistance for the solenoid coils is
identified below:
Solenoid Valve Coil
PRV1 and PRV2 (deck)
SV1 and PRV (lift)
SV2 (lift)
6. If solenoid coil resistance is incorrect, replace sole-
noid (see Hydraulic Solenoid Valve Coil Removal and
Installation in the Service and Repairs section of this
chapter).
Electrical System
Resistance
7.1 ohms
7.1 ohms
8.7 ohms
Page 5 - - 38
NOTE: The two (2) solenoid valve coils on the deck
control manifold (PRV1 and PRV2) are identical. Sole-
noid valve coils SV1 and PRV on the lift control manifold
are identical and are the same as those used on the
deck manifold. The remaining lift manifold coil (SV2) is
different. To assist in troubleshooting, identical coils can
be exchanged. If the problem follows the exchanged
coil, an electrical problem likely exists with the coil. If the
problem remains unchanged, something other than the
solenoid coil is the problem source (e.g. switch, circuit
wiring, hydraulic problem).
7. Connect wire harness electrical connector to the so-
lenoid valve coil after testing is completed.
8. Lower and secure seat if deck control manifold was
accessed. Install operator floor plate if lift control man-
ifold was accessed.
1
FRONT
Figure 46
1. Deck control manifold
2. PRV2 solenoid
2
3
FRONT
Figure 47
1. Lift control manifold
2. SV1 solenoid
3
2
3. PRV1 solenoid
4
1
3. SV2 solenoid
4. PRV solenoid
Groundsmaster 4300--D