Solenoid Valve Coils - Toro 04384 Service Manual

Solenoid Valve Coils

The Greensmaster hydraulic control manifold uses sev-
eral hydraulic solenoid valve coils for system control.
When the solenoid coils are energized, hydraulic valve
shift occurs to control hydraulic circuit flow. Testing of the
coils can be done with the coil installed on the hydraulic
valve.
Testing
1. Determine solenoid coil(s) that is to be tested and lo-
cate coil on hydraulic manifold (Fig. 17). Disconnect har-
ness electrical connector from solenoid valve coil.
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 solenoid coil being
testing.
NOTE: Solenoid coil resistance should be measured
with solenoid at approximately 68
may be slightly different than listed at different tempera-
tures. Typically, a failed solenoid coil will either be
shorted (very low or no resistance) or open (infinite re-
sistance).
2. Using a multimeter (ohms setting), measure resis-
tance between the two (2) connector terminals on the
solenoid valve coil. The resistance for the solenoid coils
is identified below:
Solenoid Valve Coil
S1R1 and S3
S2 and S4
3. If solenoid coil resistance is incorrect, replace sole-
noid coil (refer to control manifold service procedures in
the Service and Repairs section of Chapter 4 -- Hydrau-
lic System).
NOTE: To assist in troubleshooting, identical solenoid
valve 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). The control
manifold S1R1 coil is the same as the manifold S3 coil.
The manifold S2 and S4 coils are identical.
4. After coil testing is completed, connect wire harness
electrical connector to the solenoid valve coil.
5. Secure all machine components that were removed
to access hydraulic manifold.
Greensmaster 3250--D
o o
F (20 C). Resistance
Resistance
7.1 ohms
8.6 ohms
Page 5 - - 17
4
2
Figure 17
1. Solenoid S1R1
2. Solenoid S2
3
1
3. Solenoid S3
4. Solenoid S4
Electrical System