Toro Pro Sweep 07066 Service Manual page 67

The Up Function Select relay is used to control the ener-
gizing of hydraulic manifold solenoid (SV3) to raise the
sweeper. When the Up Function Select relay is not ener-
gized, solenoid (SV3) can be energized by the operator
for the hopper dump function. When the Up Function
Select relay is energized, solenoid (SV3) can be ener-
gized by the operator for the sweeper up function.
The Hopper Height Select relay is used control the
height that the hopper can be raised. When the Hopper
Height Select relay is not energized (sweeper is offset
so hitch home proximity switch is open), the hopper can
only be raised to the turn--around position. When the
Hopper Height Select relay is energized (hitch home
proximity switch is closed), the hopper can be raised to
the transport position and the hopper dump function is
allowed.
The Hitch Home Verify for Dump relay is used to prevent
the hopper dump function when the sweeper is offset
(not directly behind the tow vehicle). When the Hitch
Home Verify for Dump relay is not energized (sweeper
is offset so hitch home proximity switch is open), the
hopper dump function is disabled. When the Hitch
Home Verify for Dump relay is energized (hitch home
proximity switch is closed), the hopper dump function is
allowed.
The Offset Lockout relay is used to prevent offsetting the
sweeper when the dump hopper is raised. When the Off-
set Lockout relay is not energized (hopper raised so off-
set lockout proximity switch is open), sweeper offset
(both right and left) is disabled. The energized Offset
Lockout relay also causes the dump beeper to sound.
When the Offset Lockout relay is energized (hopper low-
ered so offset lockout proximity switch is closed),
sweeper offset is allowed.
Relay Testing
1. Position sweeper on a level surface with dump hop-
per lowered. If sweeper is attached to towing vehicle,
apply vehicle parking brake, stop engine and remove
key from the ignition switch. To ensure that electrical
power is removed from Pro Sweep, disconnect sweeper
power harness from tow vehicle.
2. Remove cover from frame to access relays (Fig. 8).
3. Locate relay that is to be tested. Disconnect wire har-
ness connector from relay. Remove relay from mounting
bracket for testing.
NOTE: Prior to taking small resistance readings with a
digital multimeter, short the meter test leads together.
The meter will 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 from the measured value of the component you
are testing.
Pro Sweep
4. Verify coil resistance between terminals 85 and 86
with a multimeter (ohms setting). Resistance should be
from 70 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
applied 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 voltage and multimeter leads from the
relay terminals.
9. Secure relay to mounting bracket and connect wire
harness connector to relay.
10.Secure cover to frame. Connect sweeper power har-
ness to tow vehicle.
1. Coil terminal
2. Common terminal
Page 4 - - 11
4
3
1
86 87A 87
85 30
1
2
Figure 9
3. Normally closed term.
4. Normally open term.
Electrical System